In phonetics, downstep is a phonemic or phonetic downward shift of tone between the syllables or words of a tonal language. It is best known in the tonal languages of West Africa, but the pitch accent of Japanese (a non-tonal language) is quite similar to downstep in Africa. Downstep contrasts with the much rarer upstep. The symbol for downstep in the International Phonetic Alphabet is a superscript down arrow, ꜜ (↓). It is common to see a superscript exclamation mark, ꜝ (!), used instead due to typographic constraints.
Phonetic downstep may occur between sequences of the same phonemic tone. For example, when two mid tones occur together in Twi, the second is at a lower pitch than the first. Thus downstep plays a vital role in downdrift and tone terracing.
Phonemic downstep may occur when a low tone is elided, or occurs as a floating tone, and leaves a following tone at a lower level than it would otherwise be. An example occurs in Bambara. In this language, the definite article is a floating low tone. With a noun in isolation, it docks to the preceding vowel, turning a high tone into a falling tone:
However, when it occurs between two high tones, it downsteps the following tone:
it's not a river
/bá ꜜ tɛ́/
it's not the river
Japanese pitch accent is similar. About 80% of Japanese words have an evenly rising pitch, something like French, which carries over onto following unstressed grammatical particles. However, a word may have a drop in pitch between morae, or before the grammatical particle. An example is
In isolation like this, the first word has a high-low pitch, whereas the second and third are homonyms with a low-high pitch. (The first syllable is only low when the word is said in isolation.) However, all three are distinct when followed by the so-called "subject" particle ga: