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

"This sucks!."

verb: attract by using an inexorable force, inducement, etc.

"The current boom in the economy sucked many workers in from abroad."