Heptad

n.

1.

(Chem.) An atom which has a valence of seven, and which can be theoretically combined with, substituted for, or replaced by, seven monad atoms or radicals; as, iodine is a heptad in iodic acid. Also used as an adjective.

Noun

1.

heptad - the cardinal number that is the sum of six and one Synonyms: 7, septet, seven, sevener, VII

7, digit, figure, septet, seven, sevener, VII