LATCHSTRING

latchstring

(noun) opener consisting of a string that can be passed through a hole in a door for raising the latch from outside

Source: WordNet® 3.1

Etymology

Noun

latchstring (plural latchstrings)

A string attached to a latch allowing it to be disengaged from the opposite side.

Source: Wiktionary

Latch"string`, n.

Definition: A string for raising the latch of a door by a person outside. It is fastened to the latch and passed through a hole above it in the door. To find the latchstring out, to meet with hospitality; to be welcome. (Intrusion is prevented by drawing in the latchstring.) [Colloq. U.S.]

Source: Webster’s Unabridged Dictionary 1913 Edition