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ruby
ruby character; small hiragana or katakana readings of kanji usually above or to the side of the kanji (esp. used by printers and in ref. to printed material)
Ruby (programming language)
深紅のルビーが輝いている。
The deep red ruby is shining.
ルビーは七月の誕生石だ。
Ruby is July's birthstone.
ルビーの指輪を贈られた。
Was given a ruby ring.