[more inappropriate; most inappropriate]
: not right or suited for some purpose or situation : not appropriate or suitable
We won't tolerate such inappropriate behavior/conduct/language.
Her informal manner seemed wholly/entirely inappropriate to/for the occasion.
The movie's subject matter is inappropriate for small children (to see). = It's inappropriate for small children to see the movie. = It's inappropriate that small children should see the movie.
— inappropriately adverb
They were dressed inappropriately for such a formal affair.
— inappropriateness noun [noncount]
We were shocked by the inappropriateness of his comments.