n. 1. a function of self latching hardware which allows a lock to be set in a non-latching mode 2. A function of a door closer, or separate hardware device, which allows the door to be retained in an open position hold open arm n. a door closer arm with the capability of maintaining the door in the open position hold open cylinder n. a cylinder provided with a special cam which will hold a latch bolt in the retracted position when so set by the key