Definition of "Suck" :
noun: the act of sucking
verb: draw into the mouth by creating a practical vacuum in the mouth
"Suck the poison from the place where the snake bit."
verb: give suck to
"The wetnurse suckled the infant."
verb: take in, also metaphorically
verb: draw something in by or as if by a vacuum
"Mud was sucking at her feet."
verb: provide sexual gratification through oral stimulation
verb: be inadequate or objectionable
verb: attract by using an inexorable force, inducement, etc.
"The current boom in the economy sucked many workers in from abroad."