Uncool (adjective)

Not fashionable or admirable; unfashionable; unappealing.

Origin:

From un- (not) + cool (fashionable or admirable).

Examples:

1. He was considered uncool by his peers.
2. The uncool clothes made him stand out in a bad way.
3. His uncool behavior made him unpopular.
4. The uncool music was not well received.
5. She thought the party was uncool and left early.