▪ I.coolwortHerb.|ˈkuːlwɜːt| [See wort.] A North American herb (family Saxifragaceæ). 1860Bartlett Dict.Amer., Coolwort (Tiarella cordifolia), the popular name of an herb, the properties of which are diuretic and tonic..prepared for sale by the Shakers. ▪ II.coolwort obs.f. colewort.