"kind of fodder plant, vetch," early 14c., perhaps cognate with Middle Dutch tarwe "wheat," from Proto-Germanic *tarwo, cognate with Breton draok, Welsh drewg "darnel," Sanskrit durva "a kind of millet grass," Greek darata, daratos "bread," Lithuanian dirva "a wheat-field." Used in 2nd Wyclif version (1388) of Matt. xxiii:25 to render Greek zizania as a weed among corn (earlier darnel and cockle had been used in this place); hence figurative use for "something noxious sown among something good" (1711).
"difference between gross and net weight," late 15c., from Middle French tare "wastage in goods, deficiency, imperfection" (15c.), from Italian tara, from Arabic tarah, literally "thing deducted or rejected," from taraha "to reject."
the bearded darnel, mentioned only in Matt. 13:25-30. It is the Lolium temulentum, a species of rye-grass, the seeds of which are a strong soporific poison. It bears the closest resemblance to wheat till the ear appears, and only then the difference is discovered. It grows plentifully in Syria and Palestine.