interjection

1. Used to indicate acknowledgement or acceptance.

   “I promise to give it back. – OK.”

2. Used to introduce a sentence in order to draw attention to the importance of what is being said.

   “OK, I'm thinking of a number…”

3. Used in turn-taking, serving as a request to the speaker to grant the turn to the interrupter.

   “You always do this to me! When we were at your mother’s, you said that… – OK, OK, …”

Synonyms: 'kay, A-OK, all right, k, m'kay, okeh, okey, okey-dokey