1.verbTo make a bluff; to give the impression that one's hand is stronger than it is.
"John bluffed by betting without even a pair."
2.verb(by analogy) To frighten or deter with a false show of strength or confidence; to give a false impression of strength or temerity in order to intimidate and gain some advantage.
"The government claims it will call an election if this bill does not pass. Is it truly ready to do so, or is it bluffing?"
3.verbTo take advantage by bluffing.
"We bluffed our way past the guards."
4.verbTo fluff, puff or swell up.
5.nounA bluff; a false expression of the strength of one's position in order to intimidate.