smile noun definition in Happiness topic from the Oxford Advanced Learner's Dictionary

smile

 noun: Happiness topic
the expression that you have on your face when you are happy, amused, etc. in which the corners of your mouth turn upwards ‘Oh, hello,’ he said, with a smile. She gave a wry smile. He had a big smile on his face. I'm going to wipe that smile off your face (= make you stop thinking this is funny).