A name applied by 16th-c. herbalists to the plant Thlaspi arvense on account of its supposed medicinal virtue; by later writers applied to Clypeola Jonthlaspi, and to Erysimum cheiranthoides.
1548. Turner, Names of Herbs, 79. Thlaspi … may be named in englishe dysh-mustard, or triacle Mustard, or Boures Mustard. Ibid. (1562), Herbal, II. 152.
1597. Gerarde, Herbal, II. xix. 205. Treacle Mustarde hath long broade leaues.
1712. trans. Pomet’s Hist. Drugs, I. 4.
1760. J. Lee, Introd. Bot., App. 330. Treacle Mustard, Thlaspi. Ibid., Treacle Mustard, Clypeola.
1856. Gray, Man. Bot. (1860), 35. Erysimum, Treacle Mustard.
1882. G. Allen, Colours Flowers, ii. 43. In treacle-mustard (Erysimum), the yellow is very pale, and the petals often become almost white.
