Synonyms for Okay (same or very similar meaning)
WordNet sense 1 (an endorsement):
o.k., okeh, okey, okWordNet sense 2 (being satisfactory or in satisfactory condition):
fine, hunky-dory, fine, all rightWordNet sense 3 (giving satisfaction):
satisfactoryWordNet sense 4 (give sanction to):
approve, sanctionWordNet sense 5 (in a satisfactory or adequate manner):
alrightFrom the ODE community, based on WordNetadd/edit