Seek to deceive, being very outspoken (5)

I believe the answer is:

bluff

I'm a little stuck... Click here to teach me more about this clue!

'outspoken' is the definition.
(synonyms)

I can't explain the remainder of the clue.

(Other definitions for bluff that I've seen before include "Steep promontory" , "Try to fool in poker game" , "Try to deceive" , "What a poker player does - or tries to" , "Challengers may call it" .)

I've seen this clue in The Irish Independent.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.