Offbeat, gender-neutral way of referring to one's ex-wife or ex-husband.
I have a special ringtone in my cell phone that's only assigned to my ex-wife's phone numbers. So, when my cell phone makes that "oink-oink-oink" sound, I say "Oh, it must be my erstwhile spouse who's calling."

ex-wife ex-husband spouse estranged wife estranged husband
by Chimpeachment April 16, 2009
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