friction

/ˈfrɪkʃən/
noun
  1. The resistance that one surface or object encounters when moving over another.
    • The friction between the car's tires and the road helps it stop when you brake.
    • Ice reduces friction, making it easy to slip and slide.
    • Rubbing your hands together creates friction, which makes them warm.
  2. Disagreement or conflict between people or groups.
    • Sharing a small apartment can cause friction between roommates.
    • There was some friction between the two coworkers over who should lead the project.
    • Friction between the neighboring countries has been growing for years.