Definitions

1. noun

A word or phrase from which another word is derived, especially a word in an earlier language that is the source of a word in a later language.

“The etymon of the English word ‘knight’ is the Old English word ‘cniht’.”

2. noun

A word or phrase that is the source of a linguistic innovation or feature.

“The etymon of the new grammatical construction is a sentence from an ancient language.”