any member of a large and diverse group of oils, fats, and fatlike substances that occur in living organisms and that characteristically are soluble in lipid solvents but only sparingly soluble in aqueous solvents, rasva lahustavas aines lahustuv, vees mittelahustuv looduslik ühend, mille hulka kuuluvad neutraalrasvad (ehk tõelised rasvad), vabad rasvhapped, vahad, steroolid, steroidid, fosfolipiidid, glükolipiidid ja lipoproteiinid