A caustic, sour, biting, or bitter quality.
The quality or state of being acid.
Sourness; tartness; sharpness to the taste.
Excessive acid quality, as in gastric secretions.
Something that is harsh and difficult to endure.
The quality of being harsh or severe in the way one speaks or behaves toward people.
An area that protrudes from a surface.
A section of a fault line with high friction, such that there is no movement along this part of the fault except during an earthquake.
The quality of being difficult or unpleasant to experience.
The quality of having a rough or uneven surface.