molecular weightmedical dictionary

The sum of the atomic weight's of all the atoms constituting a molecule; the mass of a molecule relative to the mass of a standard atom, now 12C (taken as 12.000). Relative molecular mass (Mr) is the mass relative to the dalton and has no units.

See: atomic weight.

Synonyms: molecular mass, molecular weight ratio, relative molecular mass.

Abbreviation: mol wt

Acronym: MW

(05 Mar 2000)