early 15c., " to mitigate, relieve (sorrows, suffering, etc.)," from Late Latin alleviatus, past participle of alleviare "lift up, raise," figuratively "to lighten (a burden), comfort, console," from assimilated form of Latin ad "to" (see ad-) + levis "light" in weight (from PIE root *legwh- "not heavy, having little weight"). Related: Alleviated; alleviating.