Hayagriva (Skt. Hayagrīva; Tib. རྟ་མགྲིན་, Tamdrin; Wyl. rta mgrin) — the wrathful manifestation of Avalokiteshvara who symbolizes enlightened speech, usually depicted as red in colour and with a horse's head protruding from his crown.
Hayagriva is one of the eight principal deities of Kagyé where he is referred to as Lotus-like Speech (པདྨ་གསུང་, pad+ma gsung). The instructions related to this form of Hayagriva are based on the so-called "three neighs of the horse"
- See Kongtrul (2005), p. 322
- Jamgön Kongtrul Lodrö Tayé, The Treasury of Knowledge: Systems of Buddhist Tantra, Ithaca: Snow Lion, 2005