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Watson's Biblical & Theological Dictionary [1]

The text of the Vulgate in  Ezekiel 8:14 , says, that the Prophet saw women sitting in the temple, and weeping for Adonis; but according to the reading of the Hebrew text, they are said to weep for Thamuz, or Tammuz, the hidden one. Among the Egyptians Adonis was adored under the name of Osiris, the husband of Isis. But he was sometimes called by the name of Ammuz, or Tammuz, the concealed, probably to denote his death or burial. The Hebrews, in derision, sometimes call him the dead,   Psalms 106:28;  Leviticus 19:28; because they wept for him, and represented him as dead in his coffin; and at other times they denominate him the image of jealousy,  Ezekiel 8:3;  Ezekiel 8:5 , because he was the object of the jealousy of Mars. The Syrians, Phoenicians, and Cyprians, called him Adonis; and Calmet is of opinion that the Ammonites and Moabites designated him by the name of Baal- peor.

The manner in which they celebrated the festival of this false deity was as follows: They represented him as lying dead in his coffin, wept for him, bemoaned themselves, and sought for him with great eagerness and inquietude. After this, they pretended that they had found him again, and that he was still living. At this good news they exhibited marks of the most extravagant joy, and were guilty of a thousand lewd practices, to convince Venus how much they congratulated her on the return and revival of her favourite, as they had before condoled with her on his death. The Hebrew women, of whom the Prophet Ezekiel speaks, celebrated the feasts of Tammuz, or Adonis, in Jerusalem; and God showed the Prophet these women weeping for this infamous god, even in his temple.

Fabulous history gives the following account of Adonis: He was a beautiful young shepherd, the son of Cyniras, king of Cyprus, by his own daughter Myrrha. The goddess Venus fell in love with this youth, and frequently met him on mount Libanus. Mars, who envied this rival, transformed himself into a wild boar, and, as Adonis was hunting, struck him in the groin and killed him. Venus lamented the death of Adonis in an inconsolable manner. The eastern people, in imitation of her mourning, generally established some solemn days for the bewailing of Adonis. After his death, Venus went to the shades, and obtained from Proserpine, that Adonis might be with her six months in the year, and continue the other six in the infernal regions. Upon this were founded those public rejoicings, which succeeded the lamentations of his death. Some say that Adonis was a native of Syria; some, of Cyprus; and others, of Egypt.

Hastings' Dictionary of the Bible [2]

ADONIS . The phrase rendered by EV [Note: English Version.] ‘pleasant plants,’ and by RVm [Note: Revised Version margin.] ‘plantings of Adonis’ (  Isaiah 17:10 ), alludes to the miniature gardens whose rapid decline symbolized the death of this god, or rather the spring verdure of which he is a personification. This phase of the myth, which the Greeks obtained from the Semitic Tammuz cult, through the PhÅ“nicians, where the god was worshipped under the title of Adon (‘lord’), is used by Isaiah to depict the fading hope of Israel. See Tammuz.

N. Koenig.

Webster's Dictionary [3]

(1): (n.) A youth beloved by Venus for his beauty. He was killed in the chase by a wild boar.

(2): (n.) A preeminently beautiful young man; a dandy.

(3): (n.) A genus of plants of the family Ranunculaceae, containing the pheasant's eye (Adonis autumnalis); - named from Adonis, whose blood was fabled to have stained the flower.

Holman Bible Dictionary [4]

 Isaiah 17:10

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [5]

( Σαδωνις , prob. from a Phoenician form of the Hebrew אָדוֹן , Lord), was, according to Apollodorus (3, 14, 3), the son of Cinyrus and Medane, or, according to other accounts (Hesiod and Panyasis in Apollod. ut sup. 14), of Phoenix and Alphesibcea, or of an Assyrian king, Theias, by his own daughter, Smyrna, who was changed into a myrrh-tree ( Σμύρνα ) in endeavoring to escape her father s rage on discovering the incest. The beauty of the youth made him a favorite with Venus, with whom he was permitted to spend a portion of each year after his death, which occurred from a wound by a wild boar in the chase. (See Smith s Dict. Of Class. Biog. And Mythol. s.v.) This event was celebrated by a yearly festival, originally by the Syrians, who called a river near which the fatal accident occurred (Reland, Paloest. p. 269) by his name (Robinson s Researches, new ed. 3, 606), and thence by all the nations around the Mediterranean. See Braun, Selecta Sacra, p. 376 sq,; Fickensecher, Erklar. d. Mythus Adonis (Gotha, 1800); Groddeck, Ueb. d. Fest des Adonis, in his Antiquar. Versuche (Lemberg, 1800), p. 83 sq.; Moinichen, De Adonide Phoenicum (Hafn. 1702); Maurer, De Adonide ejusque cultu (Erlang. 1782).

The Vulg. gives Adonis as a rendering for Tammuz or Thammuz ( תִּמּוּז ; Sept. Θαμμούζ ), a Syrian deity, for whom the Hebrew idolatresses were accustomed to hold an annual lamentation ( Ezekiel 8:14). This idol was doubtless the same with the Phoenician Adon or Adonis, and the feast itself such as they celebrated. Silvestre de Sacy thinks that the name Tammuz was of foreign origin, and probably Egyptian, as well as the god by whom it was borne. In fact, it would probably not be difficult to identify him with Osiris, from whose worship his differed only in accessories. The feast held in honor of Tammuz was solstitial, and commenced with the new moon of July, in the month also called Tammuz. It consisted of two parts, the one consecrated to lamentation, and the other to joy; in the days of grief they mourned the disappearance of the god, and in the days of gladness celebrated his discovery and return. Adonis or Tammuz appears to have been a sort of incarnation of the sun, regarded principally as in a state of passion and sufferance, in connection with the apparent vicissitudes in its celestial position, and with respect to the terrestrial metamorphoses produced, under its influence, upon vegetation in advancing to maturity. (See Lucian, De Dea Syra, § 7, 19; Selden, De Diis Syris, 2, 31; Creuzer, Symbolik, 4, 3.) (See Tammuz).

International Standard Bible Encyclopedia [6]

a - dō´nis  : A name for the Babylonian god Tammuz . The word occurs only in the English Revised Version, margin of  Isaiah 17:10 , where for "pleasant plants" is read "plantings of Adonis." The American Standard Revised Version rightly omits this marginal suggestion.