noun
one large animal; head (of cattle)
Counter for large animals such as horses, cattle, and elephants. Used as a noun meaning 'one head' of such animals.
See also: 頭 (とう)
牧場には牛が一頭いる。
There is one cow on the farm.
彼は競走馬を一頭飼っている。
He keeps one racehorse.
The counter suffix 頭 (とう) is used for counting large animals, while 一頭 (いっとう) is the specific number 'one head'.
Compound of 一 (いち, 'one') and 頭 (とう, counter for large animals). The reading いっとう results from a regular sound change.