Meaning

noun spring-loaded doorlock that can only be opened from the outside with a key

noun catch for fastening a door or gate; a bar that can be lowered or slid into a groove

verb fasten with a latch

originFrom Middle English lacchen (“to seize, catch, grasp”, verb), from Old English læċċan (“to grasp, take hold of, catch, seize”), from Proto-Germanic *lakjaną, *lakwijaną, *lakkijaną (“to seize”), from Proto-Indo-European *(s)leh₂g-, *(s)leh₂gʷ- (“to take, seize”). Cognate with Middle Dutch lakken (“to grasp, catch”).

Etymology from Wiktionary, CC BY-SA 3.0