c.1374, "to cause trouble, grief, or vexation," from O.Fr.
molester (12c.), from L.
molestare "to disturb, trouble, annoy," from
molestus "troublesome," perhaps related to
moles "mass" (see
mole (3)) on notion of either "burden" or "barrier." Meaning "sexually assault" first attested 1950.
Molestation meant "the harassing of a person in his possession or occupation of lands" in Scot. law from 1456; in Eng. common law it came to mean "injury inflicted upon another."