noun, plural: polar molecules. A molecule with a net dipole as a result of the opposing charges (i.e. having partial positive and partial negative charges) from polar bonds arranged asymmetrically. Supplement. Molecules can either be polar or nonpolar depending on the arrangement of bonds producing a net dipole.Water is an example of a polar molecule since it has a slight positive charge on one side and a slight negative charge on the other. The dipoles do not cancel out resulting in a net dipole.Synonym: 1  dipole. molecule with a net dipole as a result of the opposing charges (i.e. having partial positive and partial negative charges) from polar bonds arranged asymmetrically. Supplement. Molecules can either be polar or nonpolar depending on the arrangement of bonds producing a net dipole.