lubricant

noun

lu·​bri·​cant ˈlü-bri-kənt 

1

: a substance (such as grease) capable of reducing friction, heat, and wear when introduced as a film between solid surfaces

2

: something that lessens or prevents friction or difficulty

a social lubricant

lubricant adjective

Examples of lubricant in a Sentence

The car's axles need more lubricant.

using humor as a social lubricant

Recent Examples on the Web

Their process uses an inexpensive catalyst that selectively breaks down the most common single-use kind of plastics into liquid oils and waxes that can be upcycled into lubricants and fuels. —Abhimanyu Ghoshal, New Atlas, 7 Sep. 2025

In another development, Northwestern University chemists developed a groundbreaking method that skips the time-consuming step of sorting plastics and directly converts stubborn single-use plastics into useful products like fuels, waxes, and lubricants. —Aman Tripathi, Interesting Engineering, 3 Sep. 2025

Massive lava beds resting on loosely consolidated volcanic debris can be unstable, and the presence of water often acts as a lubricant, triggering landslides and debris flows. —David Bressan, Forbes.com, 2 Sep. 2025

One of the guests makes a disgusting joke involving the boat and lubricant. —Rafaela Bassili, Vulture, 26 Aug. 2025

Word History

Etymology

lubric(ate) + -ant entry 1

First Known Use

circa 1828, in the meaning defined at sense 1

Kids Definition

lubricant

noun

lu·​bri·​cant ˈlü-bri-kənt 

: something (as a grease or oil) capable of reducing friction when applied between moving parts

lubricant adjective

Medical Definition

lubricant

1 of 2 adjective

lu·​bri·​cant ˈlü-bri-kənt 

: serving to lubricate a surface or part

lubricant

2 of 2 noun

: a substance that serves to lubricate a surface or part

normally, the intestinal passage requires no artificial lubricant

—E. B. Steen & Ashley Montagu