A smirk is a smile evoking insolence, scorn, or offensive smugness, falling into the category of what Desmond Morris described as Deformed-compliment Signals.^[1]

A smirk may also be an affected, ingratiating smile,^[2] as in Mr Bennet's description of Mr Wickham as making smirking love to all his new in-laws in the novel Pride and Prejudice.^[3]

The word derives from Old English smearcian, via Middle English smirken. It is from the same root as smile, from Proto-Germanic *smar-, but with a velar root extension -k- (with intensive or frequentative function) particular to English also found in talk (from the root of tell) and stalk (from the root of steal) etc.

The specific meaning of a mocking or unpleasant, malicious smile or grin develops in Early Modern English, but until the 18th century, it could still be used in the generic sense "to smile".^[4]

George Puttenham in the 16th century described what he called “a mock with a scornful countenance as in some smiling sort looking aside”.^[5]

"A constant smirk upon the face, and a whiffling activity of the body, are strong indications of futility," the Earl of Chesterfield once wrote in a letter to his son.^[6]

German-born psychiatrist Fritz Perls considered the most difficult patients to be the clever know-it-alls, recognisable by what he called “a specific kind of smile, a kind of smirk, a smirk that says, 'Oh, you're an idiot! I know better. I can outwit you and control you'”.^[7]

Look up smirk in Wiktionary, the free dictionary.

• Schadenfreude
• Sneer