(1):

(n.) Roughness to the taste; sourness; tartness.

(2):

(n.) Moral roughness; roughness of manner; severity; crabbedness; harshness; - opposed to mildness.

(3):

(n.) Sharpness; disagreeableness; difficulty.

(4):

(n.) Roughness or harshness of sound; that quality which grates upon the ear; raucity.

(5):

(n.) Roughness of surface; unevenness; - opposed to smoothness.