A hydrophobic substance is repelled by water; literally, hydrophobe means something with a fear of water.
Superhydrophobic surfaces such as the leaves of the lotus plant have surfaces that are highly hydrophobic, i.e., extremely difficult to wet.
By rubbing your finger with superhydrophobic aerogel powder you can make it superhydrophobic. Then, when sticking the finger into water no water droplet will stick on the finger. All water is completely repelled. A thin air layer forms between the finger and the water.
