1. an earlier form of a word in the same language or in an ancestor language. for example, indo-european *duwo and old english twā are etymons of modern english two.
2. A word or morpheme from which compounds and derivatives are formed.
3. A foreign word from which a particular loan word is derived. for example, latin duo, "two,” is an etymon of english duodecimal.

1. A source word of a given word.

1. an original form; primitive word; root.
2. original or fundamental signification.

1. the original element of a word; the root or primitive.
2. the original or fundamental sense; the primary or root meaning.

1. a simple form inferred as the common basis from which related words in several languages can be derived by linguistic processes