phrasal verb🧩 phrasal verb

lock up

to secure with lock

What it means

To secure a building or container with a lock, especially when leaving for the day. It can also mean to put someone in prison or to put away valuables for safekeeping.

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Examples

  • Don't forget to lock up the shop before you leave tonight.
  • She locked the documents up in the safe behind her desk.
  • He was locked up for ten years before new evidence proved his innocence.
  • I always lock up my bike, even when I'm just popping into a shop.

Where it comes from

Separable phrasal verb. The 'imprison' meaning is informal but extremely common — 'lock 'em up' became a controversial political slogan in recent decades.

Related phrasal verbs

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