室|しつshitsu[2]odaka (tail-high)

1. noun, noun (suffix)room
   先生せんせいは生徒せいと達たちに講義こうぎ室しつを退出たいしゅつさせなかった。↗

   The teacher did not permit the students to leave the lecture hall.
2. noun, noun (suffix)wife (of someone of high rank)
3. noun, noun (suffix)scabbard
4. noun, noun (suffix), astronomyChinese "Encampment" constellation (one of the 28 mansions)

• Synonym部屋へやNeutralThe everyday word for a room and the default choice in speech; 「室」 mostly appears as a suffix in set compounds such as 「会議室」 and 「研究室」.
• SynonymルームNeutralA loanword used mostly in compounds like 「ルームサービス」 and 「チャットルーム」; 「室」 is the Sino-Japanese suffix in such combinations.
• Relatedお部屋おへやNeutralThe polite form of 「部屋」, as in 「お部屋探し」; it works for your own room or someone else's, while 「室」 is mainly a suffix.
• Antonym外そとNeutralThe opposite of 「室」 in the inside–outside contrast; it refers simply to the outside.
• Antonym屋外おくがいNeutralAlso opposed to 「室」 on the inside–outside axis, but refers specifically to the outdoors, outside a building.

For an ordinary room, say 「部屋」 (or the politer 「お部屋」). Use 「室」 mainly as a suffix for functional rooms like 「教室」 and 「会議室」, and 「ルーム」 in loanword compounds like 「ロッカールーム」. 「外」 and 「屋外」 are the antonyms for outside.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 建物たてものの中なかで、壁かべや戸とで区切くぎられた空間くうかん。
2. 身分みぶんの高たかい人ひとの妻つま。
3. 刀かたななどの刃物はものを入いれる筒つつ状じょうの鞘さや。
4. 中国ちゅうごくの天文学てんもんがくの二十八にじゅうはち宿しゅくの一ひとつで、ペガスス座ぺがすすざの四辺しへん形けいの一部いちぶにあたる星宿せいしゅく。