locking up
phrasal verbUK /ˌlɒkɪŋ ˈʌp/
US /ˌlɑːkɪŋ ˈʌp/
Locking up means closing and locking a door or place so no one can get in.
The shopkeeper is locking up the store for the night.
OTHER MEANINGS
2. Putting someone in a safe place like a jail.
The police are locking up the thief.
3. Storing something safely in a locked place.
She is locking up her jewelry in the safe.
4. When a machine or joint gets stuck and cannot move.
The old wheel is locking up because it needs oil.