retail

Retail comes from the Old French verb retaillier, meaning to cut again or cut into pieces.

What began as a word for slicing something down became attached to the practice of selling goods in small quantities, rather than in bulk — the language of cutting turned into the language of commerce.

The facts at hand don't point to a specific English cognate, but the word's roots in 'cutting' suggest a family resemblance to other 'tailliers' of cloth and material, like tailor.