# hydrophobic

/hˌaɪdɹəfˈəʊbɪk/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/hydrophobic
Updated: 2026-05-19

## Definition

describing a substance that repels water. If you put oil on water, the oil stays on top because it is hydrophobic.

For teachers: having an aversion to water or being unable to mix with it. Often describes materials or surfaces that cause water to bead and roll off rather than being absorbed.

## Examples

- The wax on the car is hydrophobic.
- Scientists are developing hydrophobic coatings for medical equipment to prevent the spread of bacteria.
- The hydrophobic properties of the polymer allow it to remain dry even when submerged in a high-pressure water stream, making it ideal for underwater robotics.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.