friction

1. (physics) A force that resists the relative motion or tendency to such motion of two bodies in contact.Examples: "Secondly, When a body is once in motion it will continue to move forever, unless something stops it. When a ball is struck on the surface of the earth, the friction of the earth and the resistance of the air soon stop its motion."uncountableusually

2. (medicine, obsolete, countable) Massage of the body to restore circulation.Examples: "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."; "The frictions are made at bedtime, on a limited portion of the body, and on one side only—the calf of the leg by preference, or the thigh, groin, or axilla. It is enough to continue rubbing for from three to five minutes at most."countableobsoleteusually

3. (figuratively) Conflict, as between persons having dissimilar ideas or interests; clash.Examples: "Thais have been watching for signs of friction between the armed forces and the monarchy—the country's two biggest sources of political power—since the death in October of Bhumibol Adulyadej, King Vajiralongkorn's long-reigning father."; "Once finances are stabilised, getting Crossrail finished is Byford's most obvious task. Late and over budget, it is causing unwanted headlines and friction between the London Mayor and the Department for Transport that both sides would rather live without."figurativelyuncountableusually

4. (China, historical) (Second Sino-Japanese War) Conflict, as between the Communists and non-Hanjian Kuomintang forces.Chinahistoricaluncountableusually