Rationalization- you give an explaination to something
Minimizing- you say that wasn't important
Externalization- you say it was someone or something else's fault
Intellectualization- try to change the subject by using lengthy or "intellectual" arguements
Projection- projecting your own shortcomings on to another
Displacement-directing your feelings onto another object or person
Undoing- trying to make amends without really meaning it
Regression- returning to less mature behavior ie "he started it!"
Fantasy- going into your own world to escape the problem
Acting-out- acting with no regard for consquences
Passive-agressive- "indirectly and unassertively expressing aggression toward others"
I found these at AllAboutCounseling.com under Defense Mechanisms