finder

• POS: Noun
• HYPHEN: find=er

CIDE DICTIONARY

finder, n. 

•  One who, or that which, finds;  [1913 Webster]
•  A slide ruled in squares, so as to assist in locating particular points in the field of vision.  [Webster 1913 Suppl.]

OXFORD DICTIONARY

finder, n.
1 a person who finds.
2 a small telescope attached to a large one to locate an object for observation.
3 the viewfinder of a camera.

Idiom

finders keepers colloq. whoever finds a thing is entitled to keep it.