nymphette (n.)

late 14c., nimphe, "one of a class of semi-divine female beings in classical mythology," imagined as beautiful maidens, eternally young, from Old French nimphe (13c.) and directly from Latin nympha "nymph, demi-goddess; bride, mistress, young woman," from Greek nymphē "bride, young wife," later "beautiful young woman," then "semi-divine being in the form of a beautiful maiden;" usually said to be related to Latin nubere "to marry, wed" (see nuptial), but Beekes suggests a Pre-Greek origin.

Sub-groups include dryads, hamadryads, naiads, nereids, and oreads. The sense in English of "young and attractive woman" is attested from 1580s. Meaning "insect stage between larva and adult" is recorded from 1570s. Related: Nymphal; nymphean.