know-it-all
📖 Definitions
noun
One who acts as if they know everything, dismissing others’ ideas or advice.
💬 Usage Examples
“He shakes his head smiling. ‘Still an insufferable know-it-all.’ She gives him a taut, bitter grin. ‘And you’re still so smugly, blithely ignorant.’” Robert Jackson Bennett; City of Stairs; Crown; 2014.