Farm animal noise (3)

I believe the answer is:
moo
(Other definitions for moo that I've seen before include "Low (of cattle)" , "Cow's sound" , "Bovine low" , "Guernsey noise?" , "Cow's low" .)
I believe the answer is:
moo
(Other definitions for moo that I've seen before include "Low (of cattle)" , "Cow's sound" , "Bovine low" , "Guernsey noise?" , "Cow's low" .)