Also found in: Thesaurus, Encyclopedia.


n.1.A kind of latch whose bolt may be so locked by a detent that it can not be opened from the inside by the handle, or from the outside by the latch key.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
The deadlatch in particular needs to be maintained and is an easy target for people looking to break into your building.
You need two locks - a deadlatch cylinder lock and a five-lever mortice deadlock.