形骸|けいがいkeigai[0]heiban (flat)

1. noun(soulless) body
2. nounframework (of a building, etc.); skeleton; remains; ruin; wreck
3. nounmere shell; mere name; dead letter

• Synonym躯むくろWrittenWritten word for a lifeless body, with an archaic, literary flavor. Unlike 「形骸」, it has no figurative sense of a hollow shell that exists in name only.
• Related死体したいNeutralThe everyday, direct word for the dead body of a person or animal; plain and neutral, it is the default choice for a corpse in ordinary speech.
• Related死骸しがいWrittenWritten word for the remains of a person or animal, used most often of animals; it sounds bleaker and more desolate than 「死体」.
• Related遺体いたいFormalFormal, respectful term for a deceased person's body, common in news reports and funerals. It refers to the body itself, not 「形骸」's hollow shell.
• Related屍しかばねWrittenWritten word for a human corpse, found mostly in literature, as in 「屍を越えて」. It names the body itself, not 「形骸」's empty shell.
• Related死人しにんNeutralA plain, direct word for a person who has died, which can also mean the body itself; nothing in it softens the fact of death.
• Related亡骸なきがらWrittenWritten native-Japanese word for the body of someone who has died, carrying a note of mourning; typical when grieving a family member or someone close.
• Related遺骸いがいFormalFormal and solemn word for the remains of the deceased; it denotes the actual body, not 「形骸」's empty shell.
• Related死屍ししWrittenRare written word, used mostly in 「死屍累々」, describing corpses strewn about. Literal corpses only, not 「形骸」's figurative shell.
• Antonym実質じっしつNeutralThe actual content or substance of something, the direct opposite of 「形骸」 as an empty shell, as in 「実質的」.
• Antonym実体じったいWrittenWritten word for a real, existing entity or substance, set against 「形骸」 as mere outward form with nothing inside.
• Antonym本質ほんしつWrittenWritten word for the essential nature a thing cannot exist without, the opposite of 「形骸」's hollow outer shell.

Use 「形骸」 when rules or institutions survive in form only, often as 「形骸化する」 or 「形骸と化す」. For a corpse, everyday speech says 「死体」, formal contexts 「遺体」, and 「死人」 is just as plain; the others are written or solemn. The opposite is 「実質」.

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

1. 肉体にくたい。遺骸いがい。骨組ほねぐみ。
2. 中身なかみがなく外形がいけいだけのもの。