vanity (n.)

c. 1200, "that which is vain, futile, or worthless,"
from Old French vanite "self-conceit; futility; lack of resolve" (12c.),
from Latin vanitatem (nominative vanitas) "emptiness, aimlessness; falsity," figuratively "vainglory, foolish pride,"
from vanus "empty, void," figuratively "idle, fruitless,"
from PIE *wano-, suffixed form of root *eue- "to leave, abandon, give out."

Meaning "self-conceited" in English is attested from mid-14c.
Vanity table is attested from 1936.
Vanity Fair is from "Pilgrim's Progress" (1678).


euə-, Proto-Indo-European root meaning "to leave, abandon, give out,"
with derivatives meaning "abandoned, lacking, empty."

It forms all or part of:
avoid; devoid;
evacuate; vacant; vacate; vacation; vacuity; vacuole; vacuous; vacuum;
vain; vanish; vanity; vaunt; void;
wane; want; wanton; waste.

It is the hypothetical source of/evidence for its existence is provided by:
Sanskrit una- "deficient;"
Avestan va- "lack,"
Persian vang "empty, poor;"
Armenian unain "empty;"
Latin vacare "to be empty," vastus "empty, waste," vanus "empty, void,"
figuratively "idle, fruitless;"
Old English wanian "to lessen," wan "deficient;" Old Norse vanta "to lack."