Terminology used in describing Lewis structures of molecules
Bond pairs: An electron pair shared by two atoms in a bond.
Lone pair:  An electron pair found solely on a single atom. 
Single covalent bond - 
Bond between two atoms when they shared 1 pair
Double covalent bond –
Bond between two atoms when they shared 2 pairs.
Triple covalent bond –
Bond between two atoms when they shared 3 pairs.
Lewis Structure, Stability, Multiple Bonds, and Bond Energies
Bond order
The stability of a covalent compound is related to the bond energy.
 The magnitude of the bond energy increases and the bond length
decreases in the order:  single bond > double bond > triple bond.
Bond Energy order: single < double < triple

Bond length order: single (1) < double (2)  < triple (3)