from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Having a valency of seven
from the GNU version of the Collaborative International Dictionary of English
- adj. Having seven units of attractive force or affinity; -- said of heptad elements or radicals.
from The Century Dictionary and Cyclopedia
- In chem., equivalent to seven atoms of hydrogen in combining or saturating power: applied to an atom which can be substituted for or replaced by seven atoms of hydrogen. Also heptatomic.
From hepta- + -valent (Wiktionary)