In-admissible refers to something that is not allowed, accepted, or permitted under specific conditions or circumstances. Its antonyms are admissible, acceptable, allowed, permitted, and allowable. Admissible means something that is worthy of being considered or accepted.
Acceptable means something that is adequate, satisfactory, and favorable for use or consumption. Allowed means something that is granted or authorized by law, rules, or regulations.
Permitted means something that is allowed or granted according to formal permission or authority. Allowable means something that is within the limits of acceptability or approval under specific conditions or circumstances. All these antonyms signify that something is permissible, allowed, or acceptable.