Translation guide
Describes something lacking physical substance, solidity, or importance. Japanese uses different words for physical thinness, lack of evidence, and insignificance.
Describing objects, structures, or materials that are thin, flimsy, or not solid.
Common word for something physically thin and flimsy, often with a negative nuance of being cheap or poorly made.
This wall is so insubstantial that I can hear everything from next door.
Literally 'without substance', used for things that lack physical reality, like ghosts or illusions.
Ghosts are insubstantial beings.
Means 'thin' or 'sparse', used for gases, atmospheres, or abstract things like presence. More formal/literary.
The air at the summit is thin, and one's presence feels insubstantial.
Describing arguments, evidence, or claims that are weak, unconvincing, or not well-founded.
Literally 'thin in basis', the most natural way to say an argument or claim is insubstantial or lacks solid evidence.
The claim was insubstantial and no one believed it.
Formal word meaning 'weak' or 'feeble', often used for arguments or evidence. Common in written or academic contexts.
Means 'unconvincing', a common way to describe an insubstantial argument. Focuses on lack of persuasive power.
Describing things that are trivial, negligible, or not worth considering.
Common phrase meaning 'trivial' or 'insignificant'. Used for matters, amounts, or people considered unimportant.
Don't fight over such an insubstantial issue.
Means 'trivial' or 'minor', very common for small, insignificant matters.
There's no need to obsess over insubstantial differences.
A phrase meaning 'it's not a big deal', used to downplay something as insubstantial or unimportant.
Describing people, works, or ideas that are shallow, empty, or lack depth.
Literally 'without content', used for people, books, speeches, etc. that are insubstantial or shallow.
His talk was insubstantial and boring.
Means 'empty' or 'hollow', often used for feelings or abstract concepts. More literary.
Means 'frivolous' or 'shallow', often describing a person's character or attitude. Can be negative.
I was annoyed by his insubstantial attitude.
There is no single Japanese word that covers all senses of 'insubstantial'. Always choose based on whether you mean physically thin, lacking evidence, unimportant, or shallow. Using the wrong word can sound unnatural.
insubstantial argument (unnatural; use 根拠の薄い instead)
His rebuttal was insubstantial and didn't hold up in court.
His explanation was insubstantial and convinced no one.
That mistake is insubstantial, so don't worry about it.
The movie has beautiful visuals but its content is insubstantial.