lubricate

Everyday

1. To put oil, grease or another slippery stuff on parts of a machine so they move smoothly and do not rub or wear out. tree →
2. (science, body) To keep a part of the body moist and slippery so it moves easily, as tears lubricate the eye. tree →
3. (informal) To make something go more smoothly, like a talk or a deal. tree →

In the lessons

In science (forces) lubricating reduces friction: oil on a bike chain makes it easier to pedal. In everyday life: oiling a squeaky door hinge. In the body, joints are lubricated by fluid and eyes by tears. Phrases: «lubricate the chain», «well lubricated», «to lubricate the conversation» (informal). The noun is «lubricant», the action is «lubrication».

Examples

• Dad lubricated my bike chain with oil. tree →
• Oil lubricates the engine so the parts do not grind. tree →
• Tears lubricate your eyes when you blink. tree →
• The squeaky gate stopped squeaking after we lubricated the hinges. tree →
• Our joints are lubricated by a special fluid. tree →
• In the friction experiment, we lubricated the ramp with soapy water and the block slid faster. tree →
• A little chat about football helped to lubricate the meeting. tree →
• Never lubricate brakes, or they will not grip. tree →

Note

Regular verb: lubricated, lubricating. Related words: lubricant (the stuff), lubrication (the act). Science link: less friction, smoother movement, less heat and wear. Trap: lubricating brakes is dangerous – brakes need friction. Not a maths word.