god of the dead in Greek mythology; also the name of his realm, the abode of the dead spirits, 1590s, from Greek Haidēs, in Homer the name of the god of the underworld, son of Kronos and Rhea, brother of Zeus and Poseidon. His name is of unknown origin. Perhaps literally "the invisible" [Watkins], from privative prefix a- + idein "to see" (from PIE root *weid- "to see"). The name of the god was extended in later Greek writing to his kingdom, also "the grave, death." Related: Hadal (adj.), 1964; Hadean.

The dead seem all alive in the humane Hades of Homer, yet cannot well speak, prophesie, or know the living, except they drink blood, wherein is the life of man. And therefore the souls of Penelope's Paramours conducted by Mercury chiriped like bats, and those which followed Hercules made a noise but like a flock of birds. [Browne, "Urn-Burial," 1658]

"person; state, condition," Old English had "person, individual, character, individuality; condition, state, nature; sex, race, family, tribe;" see -hood. Obsolete after 14c. Cognate with Old Saxon hed "condition, rank, Old Norse heiðr "honor, dignity," Old High German heit, Gothic haidus "way, manner."

"collected Islamic tradition, the body of traditions relating to Muhammad," 1817, from Arabic, literally "tradition," related to hadith "new, young," hadatha "it happened, occurred," and Hebrew hadash "new." Plural is Hadithat.

by 1670s in plays, a contraction of had not.

1962, from Greek hadros "thick, bulky" (the primary sense), also "strong, great; large, well-grown, ripe," from PIE root *sa- "to satisfy." With elementary particle suffix -on. Coined in Russian as adron.

1865, from Modern Latin hadrosaurus (1859), from Greek hadros "thick, stout" (see hadron) + -saurus.

archaic second person singular of had; a contraction of haddest.

an attempt to represent the Scottish pronunciation of have.

see hematite; also see æ (1).

see hemo-; also see æ (1).