1. a submarine
Usage: informal
2. a substitute teacher
Usage: informal
3. a submarine sandwich
Usage: informal

1. to work as a substitute
Usage: informal
2. to replace someone or something
Usage: informal

Examples

• The sub surfaced near the harbor.
• We had a sub in math class today.
• I ordered a turkey sub for lunch.
• She agreed to sub for the regular teacher.
• Can you sub for me at the meeting?
• The coach decided to sub the injured player.
• The nuclear sub patrolled the coast.