Cause friction is a term used to describe a situation in which two or more people or groups are in conflict with each other. The two crossword solutions for this term are RUB and CHAFE, both of which refer to the physical act of rubbing or chafing something against another object. This physical action can be used to describe the metaphorical friction between two people or groups, as it implies that they are rubbing against each other in a way that causes discomfort or disagreement.