1580s, "discredit caused by irreligious conduct," from Middle French scandale (12c.), from Late Latin scandalum "cause for offense, stumbling block, temptation," from Greek skandalon "a trap or snare laid for an enemy," in New Testament, metaphorically as "a stumbling block, offense;" originally "trap with a springing device," from PIE *skand- "to leap, climb" (see scan (v.); also see slander (n.), which is another form of the same word).
Attested from early 13c., but the modern word likely is a reborrowing. Meaning "malicious gossip," also "shameful action or event" is from 1590s; sense of "person whose conduct is a disgrace" is from 1630s. Scandal sheet "sensational newspaper" is from 1939. Scandal-monger is from 1702.