ἐπιστροφή/epistrophē

This word is a type of thing or idea. It is a noun.

This word can mean a turning around. When used in this way, this word is used to talk about a person no longer going in one direction but now going in the opposite direction.
This word can mean conversion. Conversion is the state of a person no longer believing what is false and now believing what is true.

See: Acts 15:3