Teenager is a numeric term used to describe a person from the ages of 13 to 19 years. Although it is used to distinguish people by the decade of their life, it excludes ages 10–12 even though they are part of the same decade, since the numbers 10-12 do not include the suffix -teen. Instead, 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 the -teen numeral. The shortened form of teenager is teen, which is the only recognized form of the suffix used as a noun or adjective.
Although teenager is primarily a numeric term, it is commonly used to describe a person in the process of transitioning from childhood to adulthood while 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 human 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.
Etymology
Teenager is derived from the adjective teenage, which is named after the suffix -teen appearing in the numbers representing ages 13 to 19 and forming the name of said numerals.
Not all languages include a morpheme in their spelling of numbers 13–19, so they may not have a numeric equivalent to teenager and may use the same word for adolescent in their translation for teenager. For example, teenager in Spanish translates to adolescente the same way adolescent does, since the Spanish language does not include a morpheme in its version of numbers 13–19. Meanwhile, people in these foreign cultures may just be considered children or young adults with no recognized intermediate stage.
History
The earliest recorded usage of the word teenager in print was in 1913 in a Wilmington, Delaware newspaper called Every Evening Commercial, Wilmington Daily, where it was capitalized and treated as two separate words (Teen Ager) and used in an article about county Sunday schools. The text read, "Some of the best practical workers among 'Teen Agers' will be present and speak." However, during this time it was treated as a slang term and not recognized by the public due to its exclusive use in local newspaper articles. The word continued to be spelled this way or hyphenated in print until around 1941, where the Popular Science magazine was credited for the first usage of teenager as a singular conjoined term.
Before this, the adjective teenage gained its first recorded usage in an Evening Tribune newspaper from Albert Lea, Minnesota in 1912, where it was also treated as two separate words (teen age), similar to the later teenager. It was used in the sentence, "Margaret Slattery [...] will deliver six lectures on the development of teen age boys and girls". Much like teenager, the adjective did not see the treatment of a singular word until the early 1940s.
Even earlier, the prototype to the noun was attested teener and coined in 1894.
The noun teen in reference to a person aged 13 to 19 years dates back to 1818, where it was first used in the title of a manual handbook called Advice to the Teens, Or Practical Help to Formation of the Character, though it was extremely rare until the 20th century when the marketing concept of the teenager came to momentum.
Nevertheless, the earliest age-related terminology based on the suffix is teens, referring to the life stage. The earliest recorded usage of teens in this sense dates to the 1590s. Although, it was spelled differently as Teenes, and did not gain its modern spelling until 1664 when The Cheats was published by John Wilson. The noun teen was first recognized in a pop culture title in 1919 when the comic strip Harold Teen was published.