lock
Something used for fastening, which can only be opened with a key or combination.
Other meanings
A mutex or other token restricting access to a resource.
A segment of a canal or other navigable waterway enclosed by gates, used for raising and lowering boats between levels.
Example sentences
Word history
From Old English "loc".
Where this comes from
This definition is adapted from “lock” on Wiktionary, by its contributors; example sentences are from Tatoeba, credited to their authors above, published under CC BY-SA 4.0. This page is published under the same licence.