Lipophilicity refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. These non-polar solvents are themselves lipophilic (translated as "fat-loving" or "fat-liking"— the axiom that dissolves. Thus lipophilic substances tend to dissolve in other lipophilic substances, while hydrophilic substances tend to dissolve in water and other hydrophilic substances. Ipophilic substances interact within themselves and with other substances through the London dispersion force. They have little to no capacity to form hydrogen bonds. When a molecule of a lipophilic substance is enveloped by water, surrounding water molecules enter into an 'ice-like' structure over the greater part of its molecular surface, the thermodynamically unfavorable event that drives oily substances out of water. Being 'driven out of water' is the quality of a substance referred to as hydrophobic. Thus lipophilic substances tend to be water insoluble. They invariably have large partition coefficients.