[1] : The Collaborative International Dictionary of English v.0.48

latchstring \latch"string`\, n.
   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.
   1913 webster

   to find the latchstring out, to meet with hospitality; to
      be welcome. intrusion is prevented by drawing in the
      latchstring. colloq. u.s.
      1913 webster
see also:
to find the latchstring out 

[2] : WordNet (r) 2.0

latchstring
     n : opener consisting of a string that can be passed through a
         hole in a door for raising the latch from outside

Latchstring >> L Words
Latchstring, definition of term: Latchstring
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