friction

noun6

1. •
   The rubbing of one object or surface against another.
2. •
   (figurative) Conflict, as between persons having dissimilar ideas or interests; clash.
3. •
   (historical) Conflict during the Second Sino-Japanese War, as between the Communists and non-hanjian Kuomintang forces.
4. •
   A force that resists the relative motion or tendency to such motion of two bodies in contact.
5. •
   Any obstacle or hindrance that makes a system less convenient or desirable to use.

   • Users have reported friction from having to enter their passwords many times a day.
6. •
   (no longer used) A massage of the body to restore circulation.

   • The frictions should at first be very gentle, and performed with a view to restore heat, and not to force the blood towards the heart, which in drowned persons is already too much distended with it. — 1792