IPA: /ˈtiːneɪdʒ/
KK: /ˈtinˌeɪdʒ/
Relating to or characteristic of young people who are between the ages of 13 and 19.
Many teenage students are preparing for their final exams.
Teenage → It is formed from "teen" (a colloquial term derived from the suffix "-teen" which refers to the age range of thirteen to nineteen) and "age" (from Old French "age", meaning a period of time). The word "teenage" refers to the period of life between thirteen and nineteen years of age.
Think of the suffix "-teen" which indicates the ages from thirteen to nineteen, combined with "age" meaning a period of time — that's why teenage refers to this specific age range.