Latch/lætʃ/ Definition 1 of 5Pro Tip 1/3Physical Object Refers to a tangible part of doors or windows that secures them. He replaced the old latch with a new, shiny one. Pro Tip 2/3Manual Operation Usually requires a hand-operated action to engage or release. You need to turn the latch to open this window. Pro Tip 3/3Safety Feature Often used for childproofing or preventing accidental openings. Install a latch high up so kids can't reach it.