a facial expression characterized by turning up the corners of the mouth; usually shows pleasure or amusement

change one's facial expression by spreading the lips, often to signal pleasure

express with a smile

saber-toothed tigers

North American sabertooth; culmination of sabertooth development

a person who smiles

the human face (`kisser' and `smiler' and `mug' are informal terms for `face' and `phiz' is British)

an emoticon of a smiling face