Definition of lock
(Entry 1 of 3)
1a
: a tuft, tress, or ringlet of hair
b
locks plural
: the hair of the head
2
: a cohering bunch (as of wool, cotton, or flax) : tuft
lock
noun (2)Definition of lock (Entry 2 of 3)
1a
: a fastening (as for a door) operated by a key or a combination
b
: the mechanism for exploding the charge or cartridge of a firearm
2a
: an enclosure (as in a canal) with gates at each end used in raising or lowering boats as they pass from level to level
b
: air lock
3a
: a locking or fastening together
b
: an intricate mass of objects impeding each other (as in a traffic jam)
c
: a hold in wrestling secured on one part of the body
broadly
: a controlling hold
his paper … had a lock on a large part of the state — John Corry
4
: one that is assured of success or favorable outcome
lock
verb
locked; locking; locks
Definition of lock (Entry 3 of 3)
1a
: to fasten the lock of
b
: to make fast with or as if with a lock
lock up the house
2a
: to fasten in or out or to make secure or inaccessible by or as if by means of locks
locked himself away from the curious world
b
: to fix in a particular situation or method of operation
a team firmly locked in last place
3a
: to make fast, motionless, or inflexible especially by the interlacing or interlocking of parts
lock wheels lock a knee
b
: to hold in a close embrace
c
: to grapple in combat
also
: to bind closely
administration and students were locked in conflict
4
: to invest (capital) without assurance of easy convertibility into money
5
: to move or permit to pass (something, such as a ship) by raising or lowering in a lock
1a
: to become locked
b
: to be capable of being locked
3
: to go or pass by means of a lock (as in a canal)
lock horns
lock on
or lock onto
: to come into conflict
: to acquire (something, such as a target or signal) automatically using a sensor (such as radar)
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Merriam-Webster unabridged
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Time Traveler for lock
The first known use of lock was before the 12th century
See more words from the same century