padlock

pad|lock /p'ædlɒk/ (padlocks padlocking padlocked)
1 [N-COUNT]
A padlock is a lock which is used for fastening two things together. It consists of a block of metal with a U-shaped bar attached to it. One end of the bar is released by turning a key in the lock.
They had put a padlock on the door of his flat.
2 [VERB] V n, also V n to n
If you padlock something, you lock it or fasten it to something else using a padlock.
Eddie parked his cycle against a lamp post and padlocked it...