Unbecoming (adjective)

Not suitable or appropriate; not becoming.

Origin:

From the word become meaning "to be suitable or appropriate" and the prefix un- meaning "not".

Examples:

1. His behavior was unbecoming of a gentleman.
2. Her attire was unbecoming for a formal occasion.
3. The unbecoming language was not accepted in the office.
4. The unbecoming behavior was not tolerated in the school.
5. His attitude was unbecoming of a leader.