alto-rilievo n.

word-forming element meaning "high," sometimes also alto- (in cloud names, etc.), from Latin altus "high," literally "grown tall," from PIE root *al- (2) "to grow, nourish."

late 14c., releven, "alleviate (pain, etc.) wholly or partly, mitigate; afford comfort; allow respite; diminish the pressure of," also "give alms to, provide for;" also figuratively, "take heart, cheer up;" from Old French relever "to raise, relieve" (11c.) and directly from Latin relevare "to raise, alleviate, lift up, free from a burden," from re-, here perhaps an intensive prefix (see re-), + levare "to lift up, lighten," from levis "not heavy" (from PIE root *legwh- "not heavy, having little weight").

The notion is "to raise (someone) out of trouble." From c. 1400 as "advance to the rescue in battle, bring help to a besieged place;" also "return from battle; recall (troops)." Meaning "release from duty" is from early 15c. Related: relieved; relieving.

Proto-Indo-European root meaning "not heavy, having little weight."

It forms all or part of: alleviate; alleviation; alto-rilievo; carnival; elevate; elevation; elevator; leaven; legerdemain; leprechaun; Levant; levator; levee; lever; levity; levy (v.) "to raise or collect;" light (adj.1) "not heavy, having little weight;" lighter (n.1) "type of barge used in unloading;" lung; relevance; relevant; releve; relief; relieve.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit laghuh "quick, small;" Greek elakhys "small," elaphros "light;" Latin levare "to raise," levis "light in weight, not heavy;" Old Church Slavonic liguku, Russian lëgkij, Polish lekki, Lithuanian lengvas "light in weight;" Old Irish lu "small," laigiu "smaller, worse;" Gothic leihts, Old English leoht "not heavy, light in weight."