late 14c., "man of superhuman strength or physical courage," from Old French heroe (14c., Modern French héros), from Latin heros (plural heroes) "hero, demi-god, illustrious man," from Greek hērōs (plural hērōes) "demi-god," a variant singular of which was hērōe. This is of uncertain origin; perhaps originally "defender, protector" and from PIE root *ser- (1) "to protect," but Beekes writes that it is "Probably a Pre-Greek word."
Meaning "man who exhibits great bravery" in any course of action is from 1660s in English. Sense of "chief male character in a play, story, etc." first recorded 1690s. Hero-worship is from 1713 in reference to ancient cults and mysteries; of living men by 1830s. In Homer, of the Greeks before Troy, then a comprehensive term used of warriors generally, also of all free men in the Heroic Age. In classical mythology from at least the time of Hesiod (8c. B.C.E.) "man born from a god and a mortal," especially one who had done service to mankind; with the exception of Heracles limited to local deities and patrons of cities.
sister and wife of Zeus, the type of virtuous womanhood, from Greek Hēra, literally "protectress," related to hērōs "hero," originally "defender, protector" (see hero (n.1)).
pertaining to Herod, name of rulers in ancient Palestine in Roman times, especially Herod the Great, king of Judea 38-4 B.C.E. The name is Greek, Hērōdes, from hērōs "hero" (see hero (n.1)) + patronymic suffix -des.
1650s, "demigoddess," from Latin heroine, heroina (plural heroinae) "a female hero, a demigoddess" (such as Medea), from Greek hērōine, fem. of hērōs (see hero (n.1)). Meaning "heroic woman, woman distinguished by exalted courage or noble achievements" is from 1660s. Sense of "principal female character in a drama, poem, etc." is from 1715.
1540s, "having or displaying the qualities of a hero," shortened from heroical (early 15c., also heroycus) "noble, magnanimous," from Latin heroicus "of a hero, heroic, mythical," from Greek hērōikos "of or for a hero, pertaining to heroes," from hērōs (see hero (n.1)). In some modern uses, "having recourse to extreme measures." The Heroic Age, semi-mythical prehistoric period in Greece, ended with the return of the armies from the fall of Troy. Related: Heroically. Heroic verse (1610s), decasyllabic iambic, is from Italian.
1898, from German Heroin, coined 1898 as trademark registered by Friedrich Bayer & Co. for their morphine substitute. According to tradition the word was coined with chemical suffix -ine (2) (German -in) + Greek hērōs "hero" (see hero (n.1)) because of the euphoric feeling the drug provides, but no evidence for this seems to have been found so far.
A new hypnotic, to which the name of 'heroin' has been given, has been tried in the medical clinic of Professor Gerhardt in Berlin. [The Lancet, Dec. 3, 1898]