former spouse
(10) “former spouse” means a former spouse of an employee, former employee, or annuitant— (A) who has not remarried before age 55 after the marriage to the employee, former employee, or annuitant was dissolved, (B) who was enrolled in an approved health benefits plan under this chapter as a family member at any time during the 18-month period before the date of the dissolution of the marriage to the employee, former employee, or annuitant, and (C) (i) who is receiving any portion of an annuity under section 8345(j) or 8467 of this title or a survivor annuity under section 8341(h) or 8445 of this title (or benefits similar to either of the aforementioned annuity benefits under a retirement system for Government employees other than the Civil Service Retirement System or the Federal Employees’ Retirement System), (ii) as to whom a court order or decree referred to in section 8341(h) , 8345(j) , 8445 , or 8467 of this title (or similar provision of law under any such retirement system other than the Civil Service Retirement System or the Federal Employees’ Retirement System) has been issued, or for whom an election has been made under section 8339(j)(3) or 8417(b) of this title (or similar provision of law), or (iii) who is otherwise entitled to an annuity or any portion of an annuity as a former spouse under a retirement system for Government employees, except that such term shall not include any such unremarried former spouse of a former employee whose marriage was dissolved after the former employee’s separation from the service (other than by retirement); and