ENGLISH
REFERENCE

lock

n. · v.
US //ˈɫɑk// UK //lˈɒk// lock
  1. 1 fastening device (n.)
    A2 Elementary

    a device that keeps a door, window, or container closed and usually requires a key to open.

    a mechanism for securing a door, lid, or moving part, typically operated by a key, combination, or electronic signal.

    Example

    He put the key in the lock and turned it slowly to open the front door.

    Example

    The locksmith recommended a high-security deadbolt lock to ensure the warehouse remained protected against forced entry during the night.
  2. 2 hair (n.)
    B2 Upper Intermediate Literary

    a small group of hairs that grow or hang together.

    a tuft, tress, or ringlet of hair, wool, or similar fibre.

    Example

    She brushed a stray lock of hair away from her eyes.

    Example

    The locket contained a single lock of golden hair, preserved perfectly as a memento of a childhood long since passed.
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  1. 3 waterway (n.)
    B2 Upper Intermediate

    a section of a canal with gates used to raise or lower boats to different water levels.

    an enclosure in a canal or river with gates at each end, used for raising or lowering vessels between stretches of different water levels.

    Example

    The boat waited for the water to rise in the lock before moving to the next part of the canal.

    Example

    Navigating the series of narrow locks required precise steering to avoid damaging the hull against the ancient stone walls of the canal.
    • sluice
    • water gate
  2. 4 a sure thing (n.)
    C1 Advanced Informal American English

    something that is certain to happen or be successful.

    a person or thing considered a certainty for success or a specific outcome.

    Example

    With her experience, she is a lock for the promotion.

    Example

    After the incumbent's scandal, the opposition candidate was considered a lock for the seat, though the final polling suggested a tighter race.
  3. 5 to fasten (v.)
    A2 Elementary

    to close something with a lock so that it cannot be opened without a key.

    to secure a door, container, or vehicle by means of a lock; to make something immovable.

    Example

    Don't forget to lock the car when you go into the shop.

    Example

    The protocol requires the last employee on site to lock all external exits and activate the alarm system before departing.
  4. 6 to freeze in place (v.)
    B2 Upper Intermediate

    to become fixed in one position and unable to move.

    to become fixed, motionless, or jammed in a particular position.

    Example

    The wheels of the old bicycle started to lock because of the rust.

    Example

    The cold weather caused the steering mechanism to lock, forcing the driver to pull over immediately for safety.
  5. 7 computing/internet (v.)
    B2 Upper Intermediate Technical Computing

    to stop people from changing a file or posting on a website.

    to restrict access to a digital resource, such as a database record or a forum thread, to prevent concurrent modification or further input.

    Example

    The moderator had to lock the discussion because people were being rude.

    Example

    The system will automatically lock the file while it is being edited to prevent data corruption from multiple users.
Etymology 1

From Middle English lok, from Old English loc, from Proto-West Germanic lok, from Proto-Germanic luką from Proto-Indo-European *lewg- (“to bend; turn”). Cognate with Cimbrian loch, lòch (“hole”), Dutch lok (“hole”), German Loch (“hole”), German Low German Lock (“hole”), Luxembourgish Lach (“hole”), Vilamovian łöch (“hole”), Yiddish לאָך (lokh, “hole”), Danish låg (“lid, cover”), Norwegian Bokmål lokk (“lid, cover”), Norwegian Nynorsk lok, lokk (“lid, cover”). more detail The verb is from Middle English locken, lokken, louken, from Old English lūcan, Proto-West Germanic lūkan, from Proto-Germanic lūkaną. Cognate with Dutch luiken (“to close, to shut”), Danish, Norwegian Bokmål lukke (“to close, to shut”), Faroese lúka (“to end, to finish”), Icelandic ljúka (“to close, to shut”), Norwegian Nynorsk lukka (“to close, to shut”). Related to luxe via Latin.

Etymology 2

From Middle English lok, lokke, from Old English locc (“hair of the head, hair, lock of hair, curl, ringlet”), from Proto-West Germanic lokk, from Proto-Germanic lukkaz, from Proto-Indo-European lugnó-, from Proto-Indo-European lewg- (“to bend”). Cognate with Alemannic German lokha (“hair”), Dutch lok (“lock of hair, curl”), German Locke (“lock of hair, curl”), Danish lok (“lock of hair, curl”), Faroese, Icelandic lokkur (“lock of hair, curl”), Norwegian Bokmål, Norwegian Nynorsk lokk (“lock of hair, curl”), Swedish lock (“lock of hair, curl”). It has been theorised that the word may be related to the Gothic verb 𐌻𐌿𐌺𐌰𐌽 (lukan, “to shut”) in its ancient meaning "to curb".

Word family
Idioms3 entries

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