From Longman Dictionary of Contemporary Englishyakyak1 /jæk/ noun [countable] HBAan animal of central Asia that looks like a cow with long hair
Examples from the Corpus
yak• The only income is provided by the occasional sale of a yak for the equivalent of $ 100.• Eventually the scheme had to be dropped and the cattle and yaks and horses returned to the care of individual herdsmen.• The meat is fat and gristle from tough old yaks, sheep and goats.• They stayed for two weeks, grazing the yaks.yakyak2 verb (yakked, yakking) [intransitive] informalTALK TO somebody to talk continuously about things that are not very serious, in a way that is annoying→ See Verb tableExamples from the Corpus
yak• People head out, yakking about this or that shot.• Across the land, every night, teenagers are yakking online in chat rooms with friends and Net acquaintances.Origin yak1 (1700-1800) Tibetan gyak yak2 (1900-2000) From the sound of continuous talk 