Heptad
From BiblePortal Wikipedia
Webster's Dictionary [1]
(n.) 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.
The Nuttall Encyclopedia [2]
A term in chemistry to denote an atom that is the equivalent of seven atoms of hydrogen, from hepta , seven.
