Friction reducer is a term used to describe a substance or material that reduces the amount of friction between two surfaces. The three crossword solutions for this term are LUBE (4 letters), TRUCE (5 letters), and OIL (3 letters). LUBE is a lubricant, usually a liquid or gel, that is used to reduce friction between two surfaces. A TRUCE is an agreement between two parties to stop fighting or arguing. OIL is a viscous liquid derived from petroleum that is used as a lubricant and to reduce friction. All three of these solutions can be used as friction reducers.