lip·id (lĭpĭd, līpĭd) also lip·ide (lĭpīd′, līpīd′)
Any of a group of organic compounds, including the fats, oils, waxes, sterols, and triglycerides, that are insoluble in water but soluble in nonpolar organic solvents, are oily to the touch, and together with carbohydrates and proteins constitute the principal structural material of living cells.
[French lipide : Greek lipos, fat; see LIPO- + French -ide, -ide.]
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