A frown (also known as a scowl) is a facial expression in which the eyebrows are brought together, and the forehead is wrinkled, usually indicating displeasure, sadness or worry, or less often confusion or concentration.
The mouth expression is also commonly referred to in the colloquial English phrase, especially in the United States, to "turn that frown upside down" which indicates changing from sad to happy.
Charles Darwin described the primary act of frowning as the furrowing of the brow which leads to a rise in the upper lip and a down-turning of the corners of the mouth.
[3] This universality suggests a shared adaptive quality to frowning allowing for social communication of negative emotional states.
[4] Scott Fahlman first suggested the use of the colon with the left parenthesis to iconically represent a frowning face on the Internet in what has become a well-known emoticon.
When the loser of a competition frowns it increases brain responses associated with pleasure in the winner, which is possibly related to the feeling of schadenfreude experienced when witnessing the misfortune of others.