Dictionary
dou'ble bond'
Chem.
a chemical linkage consisting of two covalent bonds between two atoms of a molecule, represented in chemical formulas by two lines, two dots, or four dots, as CH
2=CH
2; CH
2:CH
2; CH
2::CH
2.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.