A thin, pointed piece of metal with a raised edge twisting around it, used to join things together.

“The wooden chair is wobbly because a screw is missing.”

To fasten or tighten something by turning it.

“Screw the cap on tightly so the juice doesn't spill.”

To make a big mistake or ruin a situation (often used as 'screw up').

“I really screwed up the interview by being late.”