noun
cow's rump
Literal meaning, rarely used outside the idiom 鶏口牛後 (better to be the head of a chicken than the rear end of a cow).
「牛後」は文字通り牛の尻を指すが、単独で使われることはほとんどない。
牛後 literally means a cow's rump, but it is almost never used by itself.
noun
low-ranking member of a large group; small fish in a big pond
Figurative use, always in the context of the proverb 鶏口となるも牛後となるなかれ (rather be the head of a chicken than the tail of a cow). Implies being an insignificant follower in a large organization.
See also: 鶏口 · 鶏口牛後 (けいこうぎゅうご)
大企業で牛後になるより、小さくても鶏口を目指したい。
Rather than being a small fish in a big company, I'd rather aim to be a big fish in a small one.
From Chinese 牛後 (niúhòu), literally 'cow's rear', used figuratively in the proverb 鶏口牛後. The Japanese reading is on'yomi.