as a noun, 'bluff' can refer to a steep cliff or bank, especially one formed by river erosion. It can also mean an act of pretending confidence in one's cards in games like poker, or more generally, an attempt to deceive someone by pretending to act confidently.
The house was built on a bluff overlooking the river.
His confident demeanor was just a bluff; he was actually very nervous.
She called his bluff when he threatened to quit.
The term 'call someone's bluff' is an idiomatic expression meaning to challenge someone to act on their threat or prove that their claim is true, believing it to be a deception. 'Bluff' in the context of geography and deception might seem unrelated, but both usages can be traced back to Dutch origins, with the former meaning 'front' or 'forehead' and the latter meaning 'to bluster.'
as an adjective, 'bluff' describes someone who is straightforward, direct, and often brusque in manner.
'Bluff' can be used to describe a person's manner or demeanor.
He has a bluff manner, but he's kind-hearted.
Her bluff approach can sometimes be off-putting to sensitive individuals.
Despite his bluff exterior, he's quite empathetic.
as a verb, 'bluff' means to deceive someone by pretending to have a strong position or to be confident in one's abilities or intentions.
He tried to bluff his way through the interview, pretending he knew more than he did.
She bluffed about having other job offers to get a higher salary.
In poker, sometimes you have to bluff to win with a weak hand.