姉し弟てい

also: きょうだい

し

て

い

Meanings

older sister and younger brother

Refers specifically to a sibling pair consisting of an older sister and a younger brother. Not used for other sibling combinations.

彼かれらは姉し弟ていで、姉あねは大だい学がく生せい、弟おとうとは高こう校こう生せいです。
They are an older sister and younger brother; the sister is a university student and the brother is a high school student.
姉し弟ていで一いっ緒しょに買かい物ものに行いった。
The older sister and younger brother went shopping together.

Kanji

姉elder sister
弟younger brother, faithful service to elders

Don't confuse with

兄けい妹まい
姉弟 is the reverse pairing—older sister and younger brother—so it's easy to mix up with 兄妹, which is older brother and younger sister.
弟てい妹まい
姉弟 refers to an older sister and younger brother, whereas 弟妹 refers to a younger brother and younger sister, making the two easy to confuse due to their similar kanji patterns.

Written forms

姉弟Usage100%
- してい
  Standard kanji spelling for the reading してい, specifically meaning an older sister and younger brother pair.
- きょうだい
  gikun (meaning-based reading) or jukujikun
  Gikun reading; the kanji 姉弟 is normally read してい. Reading it as きょうだい is a special, non-standard reading used in some contexts to emphasize the sibling relationship, but it is uncommon.
きょうだい
gikun (meaning-based reading) or jukujikun

Etymology

Compound of 姉 (older sister) and 弟 (younger brother). The reading してい is the standard on'yomi combination. The gikun reading きょうだい is a special reading applied to this kanji compound to convey the meaning of siblings, but it is not the standard reading.