Entry 1 sense Webster, 1913 Teenager /(tēn"āj`ẽr)/ · Teen·ag·er · IPA /ˈtinˌeɪ.dʒəɹ/ 01 n. a person whose age is in the teens, i.e. one between the ages of 13 to 19 inclusive. 1. a person whose age is in the teens, i.e. one between the ages of 13 to 19 inclusive.