Observador, estranho, intruso.n.
One not belonging to the concern, institution, party, etc., spoken of; one disconnected in interest or feeling.
A locksmith's pinchers for grasping the point of a key in the keyhole, to open a door from the outside when the key is inside.
A horse which is not a favorite in the betting
foreigner, stranger generic term, alien generic term, unknown generic term noun, contestant generic term