The action or fact of returning to work after having retired; an instance of this. Also: a period of time during which a person has returned to work after having retired.
Origin
1940s; earliest use found in The Chester Times. From un- + retirement.
Definition of unretirement in US English:
unretirement
noun(ˌ)ʌnrɪˈtʌɪəm(ə)nt
US
The action or fact of returning to work after having retired; an instance of this. Also: a period of time during which a person has returned to work after having retired.
Origin
1940s; earliest use found in The Chester Times. From un- + retirement.