The action of rubbing one thing upon another.

That which prevents friction.

A powder or other preparation for rubbing or cleansing the teeth; a tooth-powder or tooth-paste; also applied to liquid preparations.

A speech sound produced by forcing an air stream through a narrow opening and resulting in audible high-frequency vibrations; such as, "f" or "s".

1. The rubbing of one body (or thing) against another; attrition.
2. The resistance which any body meets with in moving over another body.
3. The rubbing of two objects against each other when one or both are moving.
4. In physics, the resistance encountered by an object moving relative to another object with which it is in contact.
5. In medicine, deliberate rubbing of a body part as a way of stimulating blood circulation, warming, or relieving pain.
6. Disagreement or conflict, stopping short of violence, between individuals, groups, or nations with differing aims or views.

Free from or without friction.