1. tending to repel or not absorb water; not wettable by water
Usage: chemistry and materials science
2. having an extreme or irrational fear of water
Usage: medical, psychology

Examples

• The coating on the fabric is hydrophobic, so water beads up and rolls off.
• Oil is hydrophobic and does not mix with water.
• Hydrophobic materials are often used in waterproof clothing.
• The lotus leaf has a naturally hydrophobic surface that keeps it dry.
• Some people with hydrophobic tendencies avoid swimming pools.
• Scientists developed a hydrophobic paint that repels moisture.