adjective
insubstantial
in-sub-STAN-shuhl/ˌɪnsəbˈstænʃl/
Without enough solid substance to have weight.
The insubstantial cardboard chair buckles beneath the weight of a small book.

Etymology
The negative prefix denies substance or reality. This can describe something without physical solidity, or figuratively something lacking the real content or importance that would give it weight.
In context
the word head or the word cut which is a universal we feel such words to be incomplete and insubstantial they seem to demand a context before anything can be done with them
More examples
- The curtains are so insubstantial that every breeze lifts them.
- An insubstantial lunch leaves me hungry all afternoon.
- Her objections seem insubstantial beside the benefits of the plan.
Forms
insubstantial
insubstantiality noun — The quality of lacking solid substance.
Similar words
- flimsy
- Emphasizes weak construction rather than a lack of substance.
- ethereal
- Suggests an airy, delicate quality rather than insufficient substance.