noun
Rare technical term for a lifebuoy; the more common word is 救命浮環 (きゅうめいふかん).
See also: 救命浮環
船には救難浮標が備え付けられていた。
The ship was equipped with lifebuoys.
救命浮環 is the standard modern term for a lifebuoy; 救難浮標 is a rare synonym.
Compound of 救難 (rescue) + 浮標 (buoy). The exact historical derivation is uncertain, but the spelling is conventionally associated with the meaning.