a mechanism for keeping a door, window, lid, or container fastened, typically operated by a key

the key turned firmly in the lock

a short section of a canal or river with gates and sluices at each end which can be opened or closed to change the water level, used for raising and lowering boats

there was a lock every quarter of a mile

the turning of the front wheels of a vehicle to change its direction of motion

a player in the second row of a scrum

a person or thing that is certain to succeed; a certainty

all of this makes him a lock to make the Hall of Fame

a mechanism for exploding the charge of a gun

fasten or secure (something) with a lock

she closed and locked her desk

restrict access to the full functionality or data of (a computer, mobile phone, file, etc.), especially by requiring a user to verify their identity with a passcode or other form of authentication

my computer is locked and I've forgotten my login info

I don't want people to read my emails—that's why I lock my phone

make or become rigidly fixed or immovable

he locked his hands behind her neck

their gaze locked for several long moments

go through a lock on a canal

we locked through at Moore Haven

a piece of a person's hair that coils or hangs together

she pushed back a lock of hair