D defs.my
Entry 1 sense Webster, 1913

Molecular

/məl-ĕk'-yəl-ẽr/ · Mo·lec·u·lar · IPA /məˈlɛk.jə.ləɹ/
01 a. Pertaining to, connected with, produced by, or consisting of, molecules; as, molecular forces; molecular groups of atoms, etc.
  1. 1.
    Pertaining to, connected with, produced by, or consisting of, molecules; as, molecular forces; molecular groups of atoms, etc.(Phys. & Chem.)
Phrases & compounds
Molecular attraction — attraction acting between the molecules of bodies, and at insensible distances.
Molecular weight — the weight of a molecule of any gas or vapor as compared with the hydrogen atom having weight of 1 as a standard; the sum of the atomic weights of the constituents of a molecule; thus, the molecular weight of water (H2O) is 18. For more precise measurements, the weight of the carbon isotope carbon-12 is used as the standard, that isotope having the value of 12.000. In this systen, now used almost universally, the hydrogen atom has a weight of 1.0079.