Hydrophobic, hydrophilic

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hydrophobic[1] materials

literally means are 'water-fearing',

practically means something that rejects water - do not dissolve, tend not to be wetted

e.g. a waterproof jacket (due to specific treatment), various bird feathers, some leaves

ultrahydrophobic

means a more unusual case of hydrophoby,

and usually refers to cases where the effect is strong enough for to bead up visibly, and roll off more quickly.

hydrophilic[2] materials are 'water-loving'

tend to be wetted by water on contact

(technically these are distinct concepts, but there are few examples of hydrophilic things that resist wetting for long)

note that that doesn't necessarily mean it is water-soluble

hygroscopic[3] refers to materials that can absorb/adsorb water and take it inside

usually meaning it can pull water from the air (so relates to to humidity, not just contact with water)

Note hygro (moisure) vs. hydro (water) -- not everything hydrophilic is also hygroscopic, but hygroscopic also means hydrophilic.

though note that due to the variation of hydrophilic-and-soluble versus hydrophilic-and-not-soluble