Buck vs. Deer What's the difference? Ask Difference. Buck noun (US) An uncastrated sheep, a ram. Deer noun (in particular) One of the smaller animals of this family, distinguished from a moose or elk. ‘I wrecked my car after a deer ran across the road.’; Buck noun A young buck; an adventurous, impetuous, dashing, or high.

Deer is a hyponym of buck. As nouns the difference between buck and deer is that buck is a male deer, antelope, sheep, goat, rabbit, hare, and sometimes the male of other animals such.