ὈνήσιμοςOnḗsimos

Onesimus: Colossians 4:9, Philemon 1:10.

Greek (New Testament) · G3682

Same root

ὀνίνημιonínēmi · G3685for which another prolonged form () is used as an alternate in some tenses (unless indeed it be identical with the base of G3686 (ὄνομα) through the idea of notoriety); to gratify, i.e. (middle voice) to derive pleasure or advantage from

Where it appears

Appears 2 times in the Bible.

Colossians 4:9 I am also sending Onesimus, a faithful and beloved brother, one of your own people. He and Tychicus will tell you everything that’s happening here.
Philemon 1:10 I appeal to you to show kindness to my child, Onesimus. I became his father in the faith while here in prison.

Source: G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922), public domain.