Again, the etymology surprised me.
(A*bey"ance) n. [OF. abeance expectation, longing; a (L. ad) + baer, beer, to gape, to look with open mouth, to expect, F. bayer, LL. badare to gape.]

1. (Law) Expectancy; condition of being undetermined.

When there is no person in existence in whom an inheritance (or a dignity) can vest, it is said to be in abeyance, that is, in expectation; the law considering it as always potentially existing, and ready to vest whenever a proper owner appears. Blackstone.

2. Suspension; temporary suppression.