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Hemlock
Hemlock [EBD]
(1.) Heb. rosh (Hos. 10:4; rendered "gall" in Deut. 29:18; 32:32; Ps. 69:21; Jer. 9:15; 23:15; "poison," Job 20:16; "venom," Deut. 32:33). "Rosh is the name of some poisonous plant which grows quickly and luxuriantly; of a bitter taste, and therefore coupled with wormwood (Deut. 29:18; Lam. 3:19). Hence it would seem to be not the hemlock cicuta, nor the colocynth or wild gourd, nor lolium darnel, but the poppy so called from its heads" (Gesenius, Lex.).
(2.) Heb. la'anah, generally rendered "wormwood" (q.v.), Deut. 29:18, Text 17; Prov. 5:4; Jer. 9:15; 23:15. Once it is rendered "hemlock" (Amos 6:12; R.V., "wormwood"). This Hebrew word is from a root meaning "to curse," hence the accursed.
HEMLOCK [SMITH]
the common ground or dwarf hemlock, a bitter, poisonous plant. The Hebrew rosh is rendered "hemlock" in two passages, (Hosea 10:4; Amos 6:12) but elsewhere "gall." [GALL] (It is possible that the plant is rather the poppy than an hemlock. --Cook.)Also see definition of "Hemlock" in Word Study