Vinegar valentines

Vinegar valentines are greeting cards, or, rather, insult cards, that come in the form of an insult, decorated with a caricature and, below that, an insulting poem. Ostensibly given on Valentine's Day, the caricature and poem is about the "type" that the recipient belongs to--spinster, floozy, dude, scholar, etc.

The cards are usually simply a sheet of thin, colored paper, about the size of a modern greeting card. They were later also produced in the form of postcards.

The cards were first produced in the late Victorian era and enjoyed their greatest popularity in that period and in the first quarter of the 20th century.

Some people mistakenly call them penny dreadfuls, although that term in fact refers to a form of potboiler fiction.

One pop culture reference to vinegar valentines is found in Bill Watterson's Calvin and Hobbes comic strip. Calvin often gives Susie Derkins vinegar valentines so as to hide his true affections for her under a veil of immature distaste.