Smile is a verb. People do it for some reasons.reason: to show people their emotion wich is happy,excited and normal. lots of people seem to do it but people dont do itall the time.
Pronunciation Key (sml)
n.
1.A facial expression characterized by an upward curving of the corners of the mouth and indicating pleasure, amusement, or derision.
2.A pleasant or favorable disposition or aspect.
1.Smile, as in Ruth was a very serious person; she rarely cracked a smile.
2.when Sarah smile she looked like an angel.
3.Grandmother smiled her consent