mid-thirties

English Thesaurus

1. the time of life between 30 and 40 (noun.time)

hypernym	:	time of life,
definition	:	a period of time during which a person is normally in a particular life state (noun.time)

part meronym	:	adulthood, maturity,
definition	:	the period of time in your life after your physical growth has stopped and you are fully developed (noun.time)