Bleat!

bleat
Pronunciation: 'blEt, Northern also 'blat, Southern usually 'blAt
Etymology: Middle English bleten, from Old English bl[AE]tan; akin to Latin flEre to weep, Old English bellan to roar

Function: verb
1 : to utter the characteristic cry of a goat or sheep

Function: noun
1 : the characteristic cry of a goat or sheep