【化】 分子量
【医】 分子量

[ noun ]
(chemistry) the sum of the relative atomic masses of the constituent atoms of a molecule
<noun.attribute>

Molecular \Mo*lec"u*lar\, a. [Cf. F. mol['e]culare. See
{Molecule}.] (Phys. & Chem.)
Pertaining to, connected with, produced by, or consisting of,
molecules; as, molecular forces; molecular groups of atoms,
etc.

{Molecular attraction} (Phys.), attraction acting between the
molecules of bodies, and at insensible distances.

{Molecular weight} (Chem.), 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.
[1913 Webster +PJC]