Teenager (word)

Teenager (shortened to teen) is a numeric term for a person from the ages of 13 to 19 years. People aged 10 to 12 years old are placed in the category of preteen, which was coined to recognize ages 10 to 12 as part of the same decade as 13-19 but linguistically separate due to the absence of -teen (They may similarly be categorized as tweens, a more neologistic term sometimes cited as starting at ages 9).

Although teenager is primarily a numeric term, it is commonly used to describe humans in the process of transitioning from childhood to adulthood (primarily 13 to 17 years old) who are experiencing the physical changes of puberty, and is conflated with adolescent. However, the developmental changes of adolescence, such as puberty (particularly in females) and the transition from primary to secondary school, typically begin around the preteens, while cognitive and physical maturation continue into the 20s. Thus, the teenage years only provide a very approximate age range of adolescence.

Despite its commonality in everyday usage, teenager is a relatively modern introduction to the English language which debuted in print around the 1910s, and did not become popular until around the late 1940s and early 1950s as a marketing neologism.