c. 1300, "female teacher, governess; supervisor of novices in a convent," from Old French maistresse "mistress (lover); housekeeper; governess, female teacher" (Modern French maîtresse), fem. of maistre "master," from Latin magister "chief, head, director, teacher" (see master (n.)).
Sense of "a woman who employs others or has authority over a household and servants" is from early 15c. Meaning "woman who has mastered an art or branch of study" is from mid-15c. Sense of "kept woman of a married man" is from early 15c. As a polite form of address to a woman, mid-15c. Meaning "woman who is beloved and courted, one who has command over a lover's heart" is from c. 1500.
1660s, "chief lady in waiting upon the queen of Spain," also "an elderly woman in charge of girls from a Spanish family," from Spanish dueña "married lady, mistress" (fem. of dueño "master"), from Latin domina "lady, mistress of the house," from Latin domus "house" (from PIE root *dem- "house, household"). Sense extended in English to "any elderly woman chaperon of a younger woman" (1708).
1887, "prostitute, immoral woman," from earlier use as a term of endearment to a girl or woman (1864), sometimes said to be a shortening of sweetheart. But another theory traces it to jam-tart (see tart (n.1)), which was British slang early 19c. for "attractive woman." Diminutive tartlet attested from 1890. To tart (something) up is from 1938. Related: Tarted.
"cute person," originally especially "attractive young woman," 1917, from diminutive of cute.