- clash, friction - a state of conflict between persons
--1 is a kind of conflict
- friction, rubbing - the resistance encountered when one body is moved in contact with another
--2 is a kind of resistance
--2 has particulars:grinding, abrasion, attrition, detrition; grip, traction, adhesive friction - friction, detrition, rubbing - effort expended in rubbing one object against another
--3 is a kind of effort, elbow grease, exertion, travail, sweat
--3 has particulars: attrition