- HEPTAD
- a term in chemistry to denote an atom that is the equivalent of seven atoms of hydrogen, from hepta, seven.
The Nuttall Encyclopaedia. James Wood. 1907.
The Nuttall Encyclopaedia. James Wood. 1907.
Heptad — Hep tad, n. [L. heptas the number seven. Gr. ?, ?, fr. epta seven.] (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 … The Collaborative International Dictionary of English
heptad — [hep′tad΄] n. [Gr heptas (gen. heptados) < hepta, SEVEN] a series or group of seven … English World dictionary
heptad — noun Etymology: Greek heptad , heptas, from hepta Date: 1660 a group of seven … New Collegiate Dictionary
heptad — /hep tad/, n. 1. the number seven. 2. a group of seven. 3. Chem. an element, atom, or group having a valence of seven. [1650 60; < Gk heptad (s. of heptás). See HEPTA , AD1] * * * … Universalium
heptad — [ hɛptad] noun technical a group or set of seven. Origin C17: from Gk heptas, heptad , from hepta seven … English new terms dictionary
heptad — hep•tad [[t]ˈhɛp tæd[/t]] n. 1) math. the number seven 2) math. a group of seven • Etymology: 1650–60; < Gk heptad , s. of heptás. See hepta , ad I … From formal English to slang
heptad — /ˈhɛptæd/ (say heptad) noun 1. the number seven. 2. a group of seven. 3. Chemistry an element, atom, or group having a valency of seven. {Late Latin heptas, from Greek: the number seven} …
Heptad repeat — The heptad repeat is an example of a structural motif which consists of a repeating pattern of amino acids: a b c d e f g H P P H P P Pwhere H represents hydrophobic residues and P represents polar residues. The positions of the heptad repeat are … Wikipedia
heptad — noun a group of seven things … Wiktionary
heptad — A septivalent chemical element or radical. * * * hep·tad (hepґtəd) any element having a valency of seven … Medical dictionary