The degree to which a substance is hydrophobic(noun)
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Use "hydrophobicity" in a sentence
"And in fact you can program the self-assembly of things, so he starts chocolate dipping edges, changing the hydrophobicity and the hydrophylicity."
"Both approaches are already working in the lab, and the primary challenges tend to involve integrating materials that have very different properties in terms of hydrophobicity, heat dissipation, etc."
"Courtney HS, Ofek I, Penfound T, Nizet V, Pence MA, et al. (2009) Relationship between expression of the family of M proteins and lipoteichoic acid to hydrophobicity and biofilm formation in Streptococcus pyogenes."