suction

Everyday

The pulling force made when air or liquid is removed from a space, so things are pulled in or held on: "A vacuum cleaner works by suction." tree →

In the lessons

In science lessons, suction is explained by air pressure: when air is taken out, the air outside pushes in. Examples are drinking through a straw, suction cups, and vacuum cleaners. In nature, octopus arms have suckers that grip by suction. Phrases: suction cup, suction pad, by suction.

Examples

• A vacuum cleaner picks up dust by suction. tree →
• The suction cup holds the hook on the window. tree →
• An octopus grips rocks with suction. tree →
• You use suction when you drink through a straw. tree →
• The dentist used a suction tube to remove the water. tree →
• A plunger unblocks a sink by suction. tree →

Note

Uncountable. Science note: suction is not really "pulling"; when air is removed, the higher air pressure outside pushes things in or holds them on. Safety: the drain in a pool can have strong suction; keep hair away from it.