al·i·bi 
(ălə-bī′)
(ălə-bī′)n. pl. al·i·bis
1. Law
a. A form of defense whereby a defendant attempts to prove that he or she was elsewhere when the crime in question was committed.
b. The fact of having been elsewhere when a crime in question was committed.
2. An explanation offered to avoid blame or justify action; an excuse.
v. al·i·bied, al·i·bi·ing, al·i·bis
v.intr.
To make an excuse for oneself.
v.tr.
To make an excuse for (another).
[Latin, elsewhere, from alius, other (on the model of ibi, there); see al-1 in the Appendix of Indo-European roots.]