The word 'vert' entered English in the late 15th century from Old French vert, meaning "green," which itself derived from Latin viridis. The Latin term can be traced back to the Proto-Indo-European root weis-, meaning "to turn, twist," which is also the source of words like 'vibrate' and 'weasel.' This connection likely stems from the concept of sap rising or life "turning" in plants, leading to the color green. In English, its primary use became specialized in heraldry for the color green, and later, through back-formation from words like 'advert,' it developed a modern informal sense for a specialist in a field.

The word 'vert' is a simplex loanword from Old French. It does not contain separable, productive morphemes in modern English.