noun, noun which may take the genitive case particle 'no'
on the verge of death; dying; moribund
Describes a person, animal, or thing that is near death or in a critical state. Often used in medical, news, or dramatic contexts. Can also be used figuratively for organizations or projects.
彼は瀕死の重傷を負った。
He was critically injured and on the verge of death.
その会社は瀕死の状態だ。
The company is in a moribund state.
危篤 is more formal and specifically refers to a critical medical condition, often used in hospital or official announcements. 瀕死 is broader and can be used figuratively.
死にかけ is a more casual, colloquial expression meaning 'almost dead' or 'dying'. 瀕死 is more formal and often used in written language.
From Chinese 瀕死 (bīnsǐ), composed of 瀕 'to approach, to be on the brink of' and 死 'death'. The reading ひんし is the on'yomi of the characters.