Dictionary definition · O.K.
noun
- an endorsement"they gave us the O.K. to go ahead"
verb
- give sanction to"I approve of his educational policies"
adjective
- being satisfactory or in satisfactory condition"an all-right movie"
adverb
- in a satisfactory or adequate manner"she'll do okay on her own"
Source: Open English WordNet (CC BY 4.0).