WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adjective.
inclined to believe or confide readily; full of trust
Word Usage
"You begin by what you call trusting a friend, that is, aiding him to self-destruction -- buying him arsenic to clear his complexion -- you end by dragging all near you into your own abyss, as a drowning man would clutch at his own brother."