1 A2 neutral
To close and lock all the doors and windows of a building before leaving.
"Can you lock up the office when you leave? I have to go early today."
separable
lock up
A2 neutral separable transitive/intransitive
To secure a building by locking all doors and windows, or to put someone in jail.
In plain English
To close and lock a place so no one can get in, or to put someone in prison.
What does "lock up" mean?
4 meanings, ordered from most common to least. Color-coded by CEFR level.
2 A2 informal
To put someone in prison or in a secure facility.
"The judge decided to lock the fraudster up for five years."
“
They're going to lock me up if they find that letter.
— Agatha Christie, 'The Murder at the Vicarage', 1930
separable
3 A2 neutral
To store something in a secure, locked place.
"She locked up her jewellery in the safe before going on holiday."
separable
4 B2 idiomatic neutral
To tie up capital or resources so they cannot be freely used (financial/figurative sense).
"Too much of their money is locked up in property that they can't easily sell."
separable
Literal vs figurative
Words literally mean
To apply a lock upward or fully — the 'up' suggests completion or totality of the securing action.
Actually means
To close and lock a place so no one can get in, or to put someone in prison.
Usage tip
Very common in everyday British and American English. When meaning 'imprison', it is often used informally or in news contexts ('they locked him up'). The noun form 'lockup' (or 'lock-up') refers to a small jail or a garage/storage unit.
Words that pair with "lock up"
Natural word combinations native speakers use most often.
house shop building criminal prisoner valuables
How to conjugate "lock up"
The five tense forms you'll use most often.
Base
lock up
I/you/we/they
3rd person
locks up
he/she/it
Past simple
locked up
yesterday
Past participle
locked up
have + pp
-ing form
locking up
continuous
Hear "lock up" in the wild
Listen to native speakers using "lock up" in real YouTube videos — click a clip to watch it on Looplines.
Keep exploring
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