/ Dictionary / Index P phospholipid bilayer: Meaning and Definition of Find definitions for: phos'pholip'id bi'layer Pronunciation: [key] a two-layered arrangement of phosphate and lipid molecules that form a cell membrane, the hydrophobic lipid ends facing inward and the hydrophilic phosphate ends facing outward. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. phospholipid phosphonium Related Content Daily Word Quiz: opulent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language