hydrophobic

hy-druh-FOH-bik /ˌhaɪ.drəˈfoʊ.bɪk/
adjectiveC1TOEFLSAT
scientifictechnical

Tending to repel or fail to mix with water.

Often used to describe surfaces that stay dry and clean because water beads up and rolls off.

The story behind the word. Combining the Greek 'hydro' (water) and 'phobos' (fear), it literally means 'water-fearing.' In chemistry, these molecules 'hide' from water by huddling together.

Word relationships

  • water-repellent: Water-repellent is a general term; hydrophobic is the precise scientific term for the molecular property.
  • hydrophilic: Having a strong affinity for water; 'water-loving'.

Commonly confused with

  • waterproof: Waterproof means water cannot penetrate; hydrophobic means the surface actively pushes water away.

Word family

  • hydrophobicity (noun): The quality of being hydrophobic.

Collocations

  • hydrophobic coating
  • hydrophobic surface
  • super-hydrophobic

Example sentences

  • "The lotus leaf is naturally hydrophobic, causing rainwater to carry away dirt as it rolls off the surface." Explaining the 'Lotus Effect'.

Memory hook

Hydro-Phobic: Water-Phobia. The material is afraid of getting wet. Water-fearing surface.

When not to use

Do not use to describe a person's fear of water (that is 'aquaphobia').

Fun facts

  • Self-cleaning paint for skyscrapers was developed by emulating the hydrophobic properties of the lotus leaf.

Related words

bio-inspired, morphology

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