An Uncle

1. The brother or brother-in-law of one’s parent.
2. (euphemistic) A companion to one's (usually unmarried) mother.
3. (figuratively) A source of advice, encouragement, or help.

Antonyms

• (with regard to gender): aunt
• (with regard to ancestry): niece, nephew

Hyponyms

• (brother of someone’s father): paternal uncle
• (brother of someone’s mother): maternal uncle
• (uncle gained by marriage): uncle-in-law