fill up verb 10forms 3 verb10 •To make (something) completely full. •To fill the tank of a vehicle with fuel.It costs a fortune these days to fill up. •To become completely full. •To satisfy the hunger of (someone).Thanks for the chocolate cake – it really filled me up! •[with oneself] To satisfy one's hunger; to stop being hungry.We've scoured these science and tapped the top experts to help you learn how to do just that. Use these seven simple strategies, and you'll fill up without filling out. — 2008 •(India, Philippines) To fill in / fill out a form etc. •To become tearful as a result of strong emotion. •(slang) To make a full house on the turn or the river. •(informal) To annoy, or displease, by taunting, or by excessive nagging.The teachers that taught me weren't cool. / You're holding me down, / Turning me 'round, / Filling me up with your rules. — 1967 •(no longer used) To make complete, to bring to a full development.Our Father’s Death Would fill up all the Guilt of Civil War, And close the Scene of Blood. — 1712 formsfilled up · filling up · fills up