lock
n. countablen. a device used to keep a door, box, or gate closed. You need a key or a combination to open it.
n. a mechanism for fastening a door, lid, or container, typically operated by a key or combination.
The front door has a strong lock.
He turned the key in the lock and pushed the heavy oak door open.
The antique chest was secured with an intricate brass lock that had resisted all attempts to be picked over the centuries.
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.
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".