middle-aged
US /ˌmɪd.əlˈeɪdʒd/
UK /ˌmɪd.əlˈeɪdʒd/

1.
mittelalt, im mittleren Alter
being in the period of life between youth and old age, usually considered to be from about 45 to 65
:
•
My parents are both middle-aged.
Meine Eltern sind beide im mittleren Alter.
•
The survey targeted middle-aged professionals.
Die Umfrage richtete sich an mittelalte Fachkräfte.