under lock and key

noun

1. a device for securing a door, gate, lid, drawer, or the like in position when closed, consisting of a bolt or system of bolts propelled and withdrawn by a mechanism operated by a key, dial, etc.
2. a contrivance for fastening or securing something.
3. (in a firearm)
   1. the mechanism that explodes the charge; gunlock.
   2. safety(def 4).
4. any device or part for stopping temporarily the motion of a mechanism.
5. an enclosed chamber in a canal, dam, etc., with gates at each end, for raising or lowering vessels from one level to another by admitting or releasing water.
6. an air lock or decompression chamber.
7. complete and unchallenged control; an unbreakable hold: The congresswoman has a lock on the senatorial nomination.
8. Slang. someone or something certain of success; sure thing: He’s a lock to win the championship.
9. Wrestling. any of various holds, especially a hold secured on the arm, leg, or head: leg lock.
10. Horology. (in an escapement) the overlap between a tooth of an escape wheel and the surface of the pallet locking it.
11. Metalworking. a projection or recession in the mating face of a forging die.

verb (used with object)

12. to fasten or secure (a door, window, building, etc.) by the operation of a lock or locks.
13. to shut in a place fastened by a lock or locks, as for security or restraint.
14. to make fast or immovable by or as if by a lock: He locked the steering wheel on his car.
15. to make fast or immovable, as by engaging parts: to lock the wheels of a wagon.
16. to join or unite firmly by interlinking or intertwining: to lock arms.
17. to hold fast in an embrace: She was locked in his arms.
18. to move (a ship) by means of a lock or locks, as in a canal (often followed by through, in, out, down, or up).
19. to furnish with locks, as a canal.

verb (used without object)

20. to become locked: This door locks with a key.
21. to become fastened, fixed, or interlocked: gears that lock into place.
22. to go or pass by means of a lock or locks, as a vessel.
23. to construct locks in waterways.

Verb Phrases

24. lock in,
    1. to commit unalterably: to lock in the nomination of the party’s candidates.
    2. (of an investor) to be unable or unwilling to sell or shift securities.
25. lock off, to enclose (a waterway) with a lock.
26. lock on, to track or follow a target or object automatically by radar or other electronic means.
27. lock out,
    1. to keep out by or as if by a lock.
    2. to subject (employees) to a lockout.
28. lock up,
    1. to imprison for a crime.
    2. Printing.to make (type) immovable in a chase by securing the quoins.
    3. to fasten or secure with a lock or locks.
    4. to lock the doors of a house, automobile, etc.
    5. to fasten or fix firmly, as by engaging parts.

Idioms

29. lock horns, to come into conflict; clash: to lock horns with a political opponent.
30. lock, stock, and barrel, completely; entirely; including every part, item, or facet, no matter how small or insignificant: We bought the whole business, lock, stock, and barrel.
31. under lock and key, securely locked up: The documents were under lock and key.

noun

1. a device fitted to a gate, door, drawer, lid, etc, to keep it firmly closed and often to prevent access by unauthorized persons
2. a similar device attached to a machine, vehicle, etc, to prevent use by unauthorized personsa steering lock
3. 1. a section of a canal or river that may be closed off by gates to control the water level and the raising and lowering of vessels that pass through it
   2. (as modifier)a lock gate
4. the jamming, fastening, or locking together of parts
5. British the extent to which a vehicle’s front wheels will turn to the right or leftthis car has a good lock
6. a mechanism that detonates the charge of a gun
7. US and Canadian informal a person or thing that is certain to win or to succeedshe is a lock for the Academy Award
8. lock, stock, and barrel completely; entirely
9. any wrestling hold in which a wrestler seizes a part of his opponent’s body and twists it or otherwise exerts pressure upon it
10. Also called: lock forward rugby either of two players who make up the second line of the scrum and apply weight to the forwards in the front line
11. a gas bubble in a hydraulic system or a liquid bubble in a pneumatic system that stops or interferes with the fluid flow in a pipe, capillary, etcan air lock

verb

12. to fasten (a door, gate, etc) or (of a door, etc) to become fastened with a lock, bolt, etc, so as to prevent entry or exit
13. (tr) to secure (a building) by locking all doors, windows, etc
14. to fix or become fixed together securely or inextricably
15. to become or cause to become rigid or immovablethe front wheels of the car locked
16. (when tr, often passive) to clasp or entangle (someone or each other) in a struggle or embrace
17. (tr) to furnish (a canal) with locks
18. (tr) to move (a vessel) through a system of locks
19. lock horns (esp of two equally matched opponents) to become engaged in argument or battle
20. lock the stable door after the horse has bolted or lock the stable door after the horse has been stolen to take precautions after harm has been done

noun

1. a strand, curl, or cluster of hair
2. a tuft or wisp of wool, cotton, etc
3. (plural) mainly literary hair, esp when curly or fine

n.1“means of fastening,” Old English loc “bolt, fastening; barrier, enclosure,” from Proto-Germanic *lukan (cf. Old Norse lok “fastening, lock,” Gothic usluks “opening,” Old High German loh “dungeon,” German Loch “opening, hole,” Dutch luik “shutter, trapdoor”). “The great diversity of meaning in the Teut. words seems to indicate two or more independent but formally identical substantival formations from the root.” The Old English sense “barrier, enclosure” led to the specific meaning “barrier on a river” (c.1300), and the more specific sense “gate and sluice system on a water channel used as a means of raising and lowering boats” (1570s). Wrestling sense is from c.1600. Phrase under lock and key attested from early 14c. n.2“tress of hair,” Old English locc “lock of hair, curl,” from Proto-Germanic *lukkoz (cf. Old Norse lokkr, Old Saxon, Old Frisian, Dutch lok, Old High German loc, German Locke “lock of hair”), from PIE *lugnos-, perhaps related to Greek lygos “pliant twig, withe,” Lithuanian lugnas “flexible.” v.“to fasten with a lock,” c.1300, from Old English lucan “to lock, to close” (class II strong verb; past tense leac, past participle locen), from the same root as lock (n.1). Cognate with Old Frisian luka “to close,” Old Saxon lukan, Old High German luhhan, Old Norse luka, Gothic galukan. Meaning “to embrace closely” is from 1610s. Related: Locked; locking. Slang lock horns “fight” is from 1839. Securely locked up, as in He keeps the wine under lock and key. [First half of 1500s] In addition to the idioms beginning with lock

lock horns

lock in

lock out

lock the barn door after the horse has bolted

lock up

also see:

under lock and key