Definify.com

Webster 1913 Edition

adv.

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Mon-

atomic

(Chem.)

(a)

Consisting of, or containing, one atom;

as, the molecule of mercury is

monatomic

(b)

Having the equivalence or replacing power of an atom of hydrogen; univalent;

as, the methyl radical is

monatomic

monatomic ‎(not comparable)

(chemistry) Of an element, consisting of a single atom in the molecule, for example, the noble gases. Note: Strictly speaking, a molecule has at least two atoms.

consisting os a single atom