(じゅうだい)

じゅうだい
noun
teens; teenage years; one's teens
1. teens; teenage years; one's teens
The period of life from age 10 to 19. Used to refer to teenage years in general or to someone who is a teenager.
十代(じゅうだい)(ころ)(おも)()す。
I recall my teenage years.
十代(じゅうだい)若者(わかもの)人気(にんき)のブランドだ。
It's a brand popular with teenagers.
彼女(かのじょ)十代(じゅうだい)後半(こうはん)からプロとして活躍(かつやく)している。
She has been active as a professional since her late teens.

十代(じゅうだい) refers to the teenage years (ages 10-19). Part of the 〜(だい) pattern used for all age decades.

AGE DECADE PATTERN:

  • 十代(じゅうだい): teens (10-19)
  • 二十代(にじゅうだい): twenties (20-29)
  • 三十代(さんじゅうだい): thirties (30-39)
  • And so on for each decade

COMMON COLLOCATIONS:

  • 十代(じゅうだい)若者(わかもの): teenagers
  • 十代(じゅうだい)(ころ): during one's teens
  • 十代(じゅうだい)前半(ぜんはん): early teens (10-14)
  • 十代(じゅうだい)後半(こうはん): late teens (15-19)

NOTE:
Unlike the English word "teenager" (13-19), 十代(じゅうだい) technically includes 10-12 year olds as well. In practice, context usually makes the intended range clear.