early 15c., from Middle French suppliant, noun use of present participle of supplier "to plead humbly, entreat, beg, pray," (Old French souploier, 12c.), from Latin supplicare "beg, beseech" (see supplication). Originally in English especially at law; sense of "humble petitioner" is from mid-16c. As an adjective, "supplicating, entreating" from 1580s. Related: Suppliance; suppliantly.