Glossary of leaf morphology

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Chart illustrating leaf morphology terms

The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular or irregular, may be smooth or bearing hair, bristles or spines. For more terms describing other aspects of leaves besides their overall morphology see the leaf article.

The terms listed here all are supported by technical and professional usage, but they cannot be represented as mandatory or undebatable; readers must use their judgement. Authors often use terms arbitrarily, or coin them to taste, possibly in ignorance of established terms, and it is not always clear whether because of ignorance, or personal preference, or because usages change with time or context, or because of variation between specimens, even specimens from the same plant. For example, whether to call leaves on the same tree "acuminate", "lanceolate", or "linear" could depend on individual judgement, or which part of the tree one collected them from. The same cautions might apply to "caudate", "cuspidate", and "mucronate", or to "crenate", "dentate", and "serrate."

Another problem is to establish definitions that meet all cases or satisfy all authorities and readers. For example, it seems altogether reasonable to define a mucro as "a small sharp point as a continuation of the midrib", but it may not be clear how small is small enough, how sharp is sharp enough, how hard the point must be, and what to call the point when one cannot tell whether the leaf has a midrib at all. Various authors or field workers might come to incompatible conclusions, or might try to compromise by qualifying terms so vaguely that a description of a particular plant practically loses its value.

Use of these terms is not restricted to leaves, but may be applied to morphology of other parts of plants, e.g. bracts, bracteoles, stipules, sepals, petals, carpels or scales. Some of these terms are also used for similar-looking anatomical features on animals.

Leaf structure[edit]

Leaves of most plants include a flat structure called the blade or lamina, but not all leaves are flat, some are cylindrical. Leaves may be simple, with a single leaf blade, or compound, with several leaflets. In flowering plants, as well as the blade of the leaf, there may be a petiole and stipules; compound leaves may have a rachis supporting the leaflets. Leaf structure is described by several terms that include:[citation needed]

Bipinnate leaf anatomy with labels showing alternative usages
A ternate compound leaf with a petiole but no rachis (or rachillae)
Image Term Latin Description
Leaf morphology Bifoliolate.png bifoliolate Having two leaflets[1]
Leaf morphology Bigeminate.png bigeminate Having two leaflets, each leaflet being bifoliolate
Leaf morphology bipinnate.png bipinnate bipinnatus The leaflets are themselves pinnately-compound; twice pinnate
Leaf morphology Biternate.png biternate With three components, each with three leaflets
Leaf morphology odd pinnate.png imparipinnate With an odd number of leaflets, pinnate with a terminal leaflet (the opposite of paripinnate)
Leaf morphology even pinnate.png paripinnate Pinnate with an even number of leaflets, lacking a terminal leaflet (the opposite of imparipinnate)
Leaf morphology Palmately compound.png palmately compound palmatus Consisting of leaflets all radiating from one point
pinnately compound pinnatus Having two rows of leaflets on opposite sides of a central axis, see imparipinnate and paripinnate
Leaf morphology Acute.png simple Leaf blade in one continuous section, without leaflets (not compound)
Leaf morphology trifoliolate.png ternate ternatus With three leaflets
trifoliate trifoliatus
trifoliolate trifoliolatus
Leaf morphology tripinnate.png tripinnate tripinnatus Pinnately compound in which each leaflet is itself bipinnate

Leaf and leaflet shapes[edit]

Being one of the more visible features, leaf shape is commonly used for plant identification. Similar terms are used for other plant parts, such as petals, tepals, and bracts.

Oddly pinnate, pinnatifid leaves (Coriandrum sativum, coriander or cilantro)
Partial chlorosis revealing palmate venation in simple leaves of Hibiscus mutabilis
Image Term Latin Refers principally to Description
Leaf morphology acicular.png acicular acicularis whole leaf Slender and pointed, needle-like
Leaf morphology acuminate.png acuminate acuminatus leaf tip Tapering to a long point in a concave manner
Leaf morphology Acute.png acute leaf tip or base Pointed, having a short sharp apex angled less than 90°
Leaf morphology Apiculate.png apiculate apiculatus leaf tip Tapering and ending in a short, slender point
Leaf morphology aristate.png aristate aristatus leaf tip Ending in a stiff, bristle-like point
asymmetrical whole leaf With the blade shape different on each side of the midrib
Leaf morphology Attenuate.png attenuate attenuatus leaf base Having leaf tissue taper down the petiole to a narrow base and always having some leaf material on each side of the petiole
Leaf morphology base auriculate (cropped).png auriculate auriculatus leaf base Having ear-shaped appendages reaching beyond the attachment to the petiole or stem (in case of a seated leaf)
Leaf morphology Caudate.png caudate caudatus leaf tip Tailed at the apex
cirrus, cirrate leaf tip Having a rachis that extends beyond the leaf blade or leaflets into a long whip-like extension or cirrus (common in climbing palms); antonym: ecirrate
Leaf morphology cordate.png cordate, cordiform cordatus whole leaf or base Heart-shaped, with the petiole or stem attached to the notch
Leaf morphology cuneate.png cuneate cuneatus leaf base Triangular, wedge-shaped, stem attaches to point
cuneiform whole leaf Narrowly triangular, widest on the opposite end from the stem, with the corners at that end rounded
Handdrawn Cuspidate.png cuspidate cuspidatus leaf tip With a sharp, elongated, rigid tip; tipped with a cusp
Leaf morphology deltoid.png deltoid, deltate deltoideus whole leaf Shaped like the Greek letter delta; triangular with stem attached to side
Leaf morphology digitate.png digitate digitatus whole leaf A palmately compound leaf with leaflets, similar to palmate[2]
ecirrate leaf tip Without a cirrus; antonym: cirrate
Leaf morphology elliptic.png elliptic ellipticus whole leaf Shaped like an ellipse (widest at mid-blade and with similar convex tappering towards apex and base), with a short or no point
Leaf morphology apex emarginate.png emarginate emarginatus leaf tip Slightly indented at the tip
Leaf morphology ensiforme.PNG ensiform ensiformis whole leaf Shaped like a sword; long and narrow with a sharp pointed tip
Leaf morphology falcate.png falcate falcatus whole leaf Sickle-shaped
Leaf morphology Fenestrate.png fenestrate fenestratus leaf surface features Large openings through the leaf; see perforate; sometimes used to describe leaf epidermal windows
Plant morphology solid filiform.png filiform filiformis whole leaf Thread- or filament-shaped
Leaf morphology flabelate.png flabellate flabellatus whole leaf Semi-circular or fan-like
Leaf morphology hastate.png hastate hastatus whole leaf or base Spear-shaped: pointed, with barbs, shaped like a spear point, with flaring pointed lobes at the base
Leaf morphology division laciniate.png laciniate lacinatus whole leaf Very deeply lobed with the lobes being very drawn out and often making the leaf look somewhat like a branch or a pitchfork
laminar 3-D shape Flat (like most leaves)
Leaf morphology lanceolate.png lanceolate lanceolatus whole leaf Long, wider in the middle, shaped like a lance tip
Leaf morphology linear.png linear linearis whole leaf Long and very narrow like a blade of grass
Leaf morphology lobed.png lobed lobatus whole leaf Being divided by clefts; may be pinnately lobed or palmately lobed
Leaf morphology Lorate.png lorate loratus whole leaf Having the form of a thong or strap
Leaf morphology Lyrate.png lyrate lyratus whole leaf Shaped like a lyre, pinnately lobed leaf with an enlarged terminal lobe and smaller lateral lobes. See also List of lyrate plants.
Leaf morphology Mucronate.png mucronate mucronatus leaf tip Ending abruptly in a small sharp point as a continuation of the midrib[3]
Leaf morphology multifide.svg multifid multi + findere whole leaf Cleft into many parts or lobes
Leaf morphology obcordate.png obcordate obcordatus whole leaf Heart-shaped, stem attaches at the tapering end
Leaf morphology oblanceolate.png oblanceolate oblanceolatus whole leaf Much longer than wide and with the widest portion near the tip; reversed lanceolate
Leaf morphology oblique.png oblique leaf base Asymmetrical leaf base, with one side lower than the other
Leaf morphology oblong.png oblong oblongus whole leaf Having an elongated form with slightly parallel sides; roughly rectangular
Leaf morphology obovate.png obovate obovatus whole leaf Teardrop-shaped, stem attaches to the tapering end; reversed ovate
obtrullate whole leaf Reversed trullate; the longer sides meet at the base rather than the apex.
Leaf morphology obtuse.png obtuse obtusus leaf tip or base Blunt, forming an angle > 90°
Leaf morphology orbicular.png orbicular orbicularis whole leaf Circular
Leaf morphology ovale.png ovate ovatus whole leaf Egg-shaped, with a tapering point and the widest portion near the petiole
Leaf morphology palmate.png palmate palmatus whole leaf Palm-shaped, i.e. with lobes or leaflets stemming from the leaf base[4]
Palmatilobé.svg palmately lobed palmatus whole leaf Lobes spread radially from a point[5]
Palmatifide.svg palmatifid palma + findere whole leaf Palm-shaped, having lobes with incisions that extend less than halfway toward the petiole
Palmatipartite.svg palmatipartite palma + partiri whole leaf Having palmate lobes with incisions that extend over halfway toward the petiole
Palmatiséquée.svg palmatisect palma + secare whole leaf Having palmate lobes with incisions that extend almost up, but not quite to the petiole.
Leaf morphology pandurate.png pandurate panduratus whole leaf Fiddle-shaped; obovate with a constriction near the middle.
Leaf morphology pedate.png pedate pedatus whole leaf Palmate, with cleft lobes[6]
Leaf morphology peltate.png peltate peltatus stem attachment A round leaf where the petiole attaches near the center, e.g. a lotus leaf
Leaf morphology attachment connate-perfoliate.png perfoliate perfoliatus stem attachment With the leaf blade surrounding the stem such that the stem appears to pass through the leaf
Leaf morphology Perforate.png perforate perforatus leaf surface features Many holes, or perforations, on leaf surface. Compare with fenestrate.
Pennatilobé.svg pinnately lobed pinna + lobus whole leaf Having lobes pinnately arranged on the central axis
Pennatifide.svg pinnatifid pinna + findere whole leaf Having lobes with incisions that extend less than halfway to the midrib
Pennatipartite2.svg pinnatipartite pinnatus + partiri whole leaf Having lobes with incisions that extend more than halfway to the midrib
Pennatiséquée.svg pinnatisect pinnatus + sectus whole leaf Having lobes with incisions that extend almost to, or up to, the midrib
Leaf morphology posture plicate.png plicate plicatus 3-D shape Folded into pleats, usually lengthwise, serving the function of stiffening a large leaf
Leaf morphology reniform.png reniform reniformis whole leaf Shaped like a kidney, with an inward curve on one side
Leaf morphology apex retuse.png retuse leaf tip With a shallow notch in a round apex
Leaf morphology rhomboid.png rhomboid, rhombic rhomboidalis whole leaf Diamond-shaped
Leaf morphology apex rounded.png rounded rotundifolius leaf tip or base Circular, no distinct point
semiterete 3-D shape Rounded on one side and flat on the other
Leaf morphology division sinuate.png sinuate sinuatus 3-D shape Circularly-lobed leaves
Leaf morphology spear-shaped.png sagittate sagittatus whole leaf Arrowhead-shaped with the lower lobes folded, or curled downward
Leaf morphology spatulate.png spatulate spathulatus whole leaf Spoon-shaped; having a broad flat end which tapers to the base
Leaf morphology hastate.png spear-shaped hastatus whole leaf See hastate.
Leaf morphology subobtuse.png subobtuse subobtusus leaf tip or base Somewhat blunted; neither blunt nor sharp
Leaf morphology subulate.png subulate subulatus leaf tip Awl-shaped with a tapering point
Plant morphology solid terete.png terete 3-D shape Circular in cross-section; more or less cylindrical without grooves or ridges
Leaf morphology trullate.png trullate whole leaf Shaped like a masonry trowel
Leaf morphology truncate.png truncate truncatus leaf tip or base With a squared-off end
undulate undulatus 3-D shape Wave-like
Leaf morphology unifoliate.png unifoliate unifoliatus compound leaves With a single leaflet; it is distinct from a simple leaf by the presence of two abscission layers and often by petiolules and stipels.


Leaf margins (edges) are frequently used in visual plant identification because they are usually consistent within a species or group of species, and are an easy characteristic to observe. Edge and margin are interchangeable in the sense that they both refer to the outside perimeter of a leaf.

Image Term Latin Description
Leaf morphology entire.png entire Forma
Even; with a smooth margin; without toothing
Leaf morphology ciliate.png ciliate ciliatus Fringed with hairs
Leaf morphology crenate.png crenate crenatus Wavy-toothed; dentate with rounded teeth
crenulate crenulatus Finely crenate
crisped crispus Curly
Leaf morphology dentate.png dentate dentatus Toothed;

may be coarsely dentate, having large teeth

or glandular dentate, having teeth which bear glands

Leaf morphology denticulate.png denticulate denticulatus Finely toothed
Leaf morphology doubly serrate.png doubly serrate duplicato-dentatus Each tooth bearing smaller teeth
Leaf morphology serrate.png serrate serratus Saw-toothed; with asymmetrical teeth pointing forward
Leaf morphology serrulate.png serrulate serrulatus Finely serrate
Leaf morphology sinuate.png sinuate sinuosus With deep, wave-like indentations; coarsely crenate
Leaf morphology lobate.png lobate lobatus Indented, with the indentations not reaching the center
Leaf morphology undulate.png undulate undulatus With a wavy edge, shallower than sinuate
Leaf morphology spiny.png spiny or pungent spiculatus With stiff, sharp points such as thistles

Leaf folding[edit]

Leaves may also be folded, sculpted or rolled in various ways. If the leaves are initially folded in the bud, but later unrolls it is called vernation, ptyxis is the folding of an individual leaf in a bud.

Image Term Latin Description
carinate or keeled carinatus With a longitudinal ridge, keel-shaped
Peperomia dolabriformis.jpg conduplicate Folded upwards, with the surfaces close to parallel
Mimetes fimbrifolius (5211424654).jpg cucullate Forming a hood, margins and tip curved downward
Involute vernation.jpg involute Rolled upwards (towards the adaxial surface)
Palm leaf washingtonia robusta.jpg plicate plicatus With parallel folds
reduplicate Folded downwards, with the surfaces close to parallel
Ledum groenlandicum.jpg revolute Rolled downwards (towards the abaxial surface)
supervolute Opposing left and right halves of lamina folded along longitudinal axis, with one half rolled completely within the other

Latin descriptions[edit]

The Latin word for 'leaf', folium, is neuter. In descriptions of a single leaf, the neuter singular ending of the adjective is used, e.g. folium lanceolatum 'lanceolate leaf', folium lineare 'linear leaf'. In descriptions of multiple leaves, the neuter plural is used, e.g. folia linearia 'linear leaves'. Descriptions commonly refer to the plant using the ablative singular or plural, e.g. foliis ovatis 'with ovate leaves'.[7]

See also[edit]


  1. ^ Radford, A.E.; Dickison, W.C.; Massey, J.R.; Bell, C.R. (1976). "Phytography - Morphological Evidence". Vascular Plant Systematics. Harper and Row, New York.
  2. ^ Index of Garden Plants, Mark Griffiths, Timber Press, 1992
  3. ^ Mucronate,, from Roget's Thesaurus.
  4. ^ "palmate (adj. palmately)". GardenWeb Glossary of Botanical Terms. iVillage GardenWeb. 2006. Archived from the original on 13 February 2009. Retrieved 19 October 2008.
  5. ^ Nelson, Randal C. (2009) [2012]. "Leaf description glossary". University of Rochester. Archived from the original on 1 August 2020. Retrieved 2 November 2017.
  6. ^ "Pedate leaf". Retrieved 24 February 2014.
  7. ^ Stearn (2004), pp. 439–440.


External links[edit]