siphon

Everyday

1. A siphon is a bent tube that moves liquid from a higher container to a lower one, over an edge, without a pump, once the tube is full. tree →
2. To siphon is to move liquid this way. tree →
3. To siphon off money or resources is to take them away bit by bit, often secretly or wrongly. tree →
4. In animals like squids and clams, a siphon is a tube used to suck in or squirt out water. tree →

In the lessons

Science: a siphon works because the liquid flowing down the longer side pulls the rest along; air pressure helps push the liquid up the short side. Everyday life: emptying a fish tank or a paddling pool with a hose. Safety: never siphon petrol by mouth, it is poisonous. News: «siphoning off money» is a kind of stealing.

Examples

• We used a siphon to empty the fish tank. tree →
• Dad siphoned the water out of the paddling pool. tree →
• The squid shoots water out of its siphon. tree →
• In science we made a siphon with a tube and two jugs. tree →
• The thief siphoned off money from the club. tree →
• The siphon only works if the end is lower than the water. tree →
• Never siphon petrol with your mouth. tree →

Note

Said «SY-fun». Spelling: siphon (more common) or syphon (also used in the UK). The ph sounds like f. A siphon needs the outlet to be lower than the surface of the liquid; it cannot lift water higher than it started.