قدح

قَدْحٌ ذ and ↓ قَادِحٌ, [the former, in the CK, in this case, erroneously, with fet-h to the د,] A canker, or corrosion, incident in trees and in teeth: (L, K:) [the former is originally an inf. n.: and] each, in the sense here expl., an epithet in which the quality of a subst. predominates: (L:) [they are therefore more properly to be expl. as meaning a thing that cankers, or corrodes: and ↓ the latter signifies also rottenness, decay, corruption, or unsoundness: (L:) and blackness that appears in the teeth: (S:) and a crack, or fissure, in wood, or in a stick, or rod; (S, L, K;) and so the former word. (K.) ― -b2- اـبْرَةُ القَدْحِ: see مِقْدَحٌ.