The state of being thin; smallness of extent from one side or surface to the opposite; as the thinness of ice; the thinness of a plate; the thinness of the skin.

Tenuity; rareness; as the thinness of air or other fluid.

A state approaching to fluidity, or even fluidity; opposed to spissitude; as the thinness of honey, of white wash or of paint.

Exility; as the thinness of a point.

Rareness; a scattered state; paucity; as the thinness of trees in a forest; the thinness of inhabitants.