buzzard

Buzzard comes from Middle English bosart, borrowed from Anglo-Norman buisart, itself from Old French busart or busard. That French word was formed by adding the suffix -ard to Old French buison or buson (the ancestor of modern French buse), which may trace back to Latin būteō, meaning 'hawk'.

The word's form shifted as it passed from Latin into Old French, then through Anglo-Norman spellings like buisart into the Middle English bosart, before settling into the modern English spelling buzzard.

The modern French word buse, meaning a bird of prey, descends from the same Old French root buison/buson that gave English its buzzard.