HEPTAD
seven, VII, sevener, heptad, septet, septenary
(noun) the cardinal number that is the sum of six and one
Source: WordNet® 3.1
Etymology
Noun
heptad (plural heptads)
A group of seven things.
(genetics) A sequence of seven bases.
Coordinate terms
• monad · duad, dyad · triad · tetrad · pentad · hexad · heptad · octad · ennead, nonad · decad, decade · hendecad · dodecad, duodecade
Anagrams
• pathed
Source: Wiktionary
Hep"tad, n. Etym: [L. heptas the number seven. Gr. "epta` seven.]
(Chem.)
Definition: 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.
Source: Webster’s Unabridged Dictionary 1913 Edition