night latch definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a door latch with a bolt opened from the outside by a key, and from the inside by a knob
night latch definition by American Heritage Dictionary
A spring lock that can be opened from the inside by turning a knob but from the outside only with a key.