[batsu ichi] – Batsu is the ‘x’ character and ichi means ‘one’. Together, batsu ichi is a colloquial word that refers to someone who has divorced their first spouse.
The word originates from how family registers are written; spouses that are removed from the register are marked with an X.
You may also see this word rendered as ×いち, ×イチ or バツイチ.
My wife and I both divorced our first spouses.