noun
crucible; melting pot
A container used for melting metals or other materials at very high temperatures. In chemistry and metallurgy contexts.
金属を溶かすために、るつぼを高温で熱した。
To melt the metal, they heated the crucible at a high temperature.
noun
melting pot (of cultures, ideas, etc.)
Figurative use: a place or situation where different cultures, ideas, or people mix together. Often used in phrases like 人種のるつぼ (racial melting pot).
ニューヨークは多様な文化のるつぼだ。
New York is a melting pot of diverse cultures.
noun
state of ecstasy; fevered excitement
Describes a state of intense excitement or ecstasy, often in a crowd or group setting. Common in expressions like 興奮のるつぼ (a cauldron of excitement).
優勝が決まった瞬間、スタジアムは興奮のるつぼと化した。
The moment the championship was decided, the stadium turned into a cauldron of excitement.
Rare kanji spelling; the reading るつぼ is a gikun/jukujikun. The on'yomi reading かんか is also possible but very uncommon.
The on'yomi reading かんか is rare and mostly used in technical or historical contexts; るつぼ is the standard reading.
The word るつぼ is thought to derive from Portuguese 'crisol' or possibly Dutch 'kroes', but the exact origin is uncertain. The kanji 坩堝 are ateji applied later.