crop (n.) Look up crop at Dictionary.com
Old English cropp "bird's craw," also "head or top of a sprout or herb." The common notion is "protuberance." Cognate with Old High German kropf, Old Norse kroppr. Meaning "harvest product" is c.1300, probably through the verbal meaning "cut off the top of a plant" (c.1200).
crop (v.) Look up crop at Dictionary.com
"cut off the top of a plant," c.1200, from crop (n.). The general meaning of "to cut off" is mid-15c. Related: Cropped; cropping. Women's fashion crop top is attested from 1984.