To show displeasure by thrusting out the lips or wearing a sullen expression. (Merriam – Webster)
To push out or purse the lips in a sexually suggestive way. (Merriam – Webster)
Having the lips sticking out, usually in order to show annoyance or to appear sexually attractive. (Collins Dictionary)
Pushing one’s lips or one’s bottom lip forward as an expression of annoyance or in order to look sexually attractive. (Oxford Dictionary)
Is the ‘fish gape’ the new way to pout?
Do You Pout Too Much? Psychology Today.
Perfecting the pout: Which city is the UK’s lip filler capital?