1520s, "state of expectation," from Anglo-French abeiance "suspension," also "expectation (especially in a lawsuit)," from Old French abeance "aspiration, powerful desire," noun of condition from abeer "aspire after, gape, open wide," from à "at" (see ad-) + ba(y)er "be open," from Latin *batare "to yawn, gape" (see abash).
Originally in French a legal term, "condition of a person in expectation or hope of receiving property;" it turned around in English law to mean "condition of property temporarily without an owner" (1650s). Hence "state of suspended action or existence." The French verb baer is also the source of English bay (n.2) "recessed space," as in bay window.
