Obs. rare. [f. UM- + STROKE sb.1] Edge, circumference.
1650. Fuller, Pisgah, I. xiv. 46. Such Towns as stand (as one may say) on tiptoes, on the very umstroke, or on any part of the utmost line of any Map. Ibid., V. xx. 182. Places situate on the Um-stroke (such the location of Aleppo in our Map) are not in their exact position.
