Ambalavasi, (Malayalam: അമ്പലവാസി; IAST:Ampalavāsi) lit. 'temple-dwelling', is a generic name for a group of castes among Hindus in Kerala, India, who render temple services. Some Ambalavasi castes are patrilineal, while the others are matrilineal. Those that practise matrilineality share many cultural similarities with the Nair caste. Their ritual rank in Hinduism lies between the Brahmin castes and the Nairs.
The Ambalavasis are broadly divided into two groups, being those who wear the sacred thread and those who do not.
Sacred thread wearers
- Pushpaka (Pushpakan Unni), who bring flowers to the temples
- Theeyatt Unni
- Marar, who act as temple musicians
- Warrier, though some families are known to conduct "yajnopaveetham" but remove the thread immediately after.
- Poduval, who works as temple watchman
The feminine names of threadless ambalavasi castes are formed by adding the suffix -syar to the masculine names as Adi-Adisyar, Pisharadi-Pisharasyar, Marar-Marasyar, Variar-Varasyar, Poduval-Poduvalsyar.
Though all Ampalavāsis have to do service in temples, they have sufficiently distinct functions to perform. Pushpakans and Nambeesans are teachers in the Pathasalas or Mutts and suppliers of flowers to temple. Chakyar stages drama. Marar serves as temple musician. Variar and Poduval did managerial and executive functions of temple committees and served as storekeepers 
Kazhakams or Ambalakkazhakams refer to associations of ambalavasi peoples in a temple to perform specific duties in the temple.
Traditionally, Ambalavasis are associated with various types of temple arts. Earlier, each of these temple arts were performed only by specific Ambalavasi castes. Now there is no community or caste barrier.
|Koodiyattam||Chakyar, Pushpakan Unni|
|Kooth||Chakyar, Nangyar (women of Nambiar)|
|Certain roles of Krishnanattam||Nambeesan or Pushpaka Unni[page needed]|
|Mizhavu (Musical Instrument)||Nambiar|
|Kuzhithalam (Musical Instrument)||Nangyar (women of Nambiar)|
|Theeyattu||Theeyatt Unni, Thiyyadi Nambiar|
|Vadyams (Musical Instruments) like
Chenda, Idakka, Udukku etc.
|Sopanasangeetham||Marar, Pothuval|
|Brahmanippattu||Brahmani (women of Nambeesan)|
They lived in villages either where the land was owned solely by one Nambudiri Brahmin family or where the land was owned by a temple, the running of which was in the control of a group of Nambudiri families. The latter villages were called sanketams.
The temples in which they worked comprised four basic types:
- Those in sanketams were large and were dedicated to deities which were worshipped throughout India, such as Shiva and Vishnu.
- Private temples, owned by Nambudiri families, which were the smaller versions of those found in the sanketams.
- The private temples of the royal lines, feudatory chiefs and vassal chiefs of what is now Kerala, which were dedicated to Bhagavati (Bhadrakali)
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- "The 'Florance' of Nangiar Koothu" (10 September 2015). Mathurubhumi Daily. 10 September 2015. Retrieved 17 February 2019. Quote: Nangyarkoothu is a traditional artform performed by the women of the Ambalavasi Nambiar community of Kerala, called Nangyaramma. However, people from other castes also has been performing the artform since the second half of the 20th century.
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