insubstantial

Adjective

Lacking substance; not real or strong.

Japanese Meaning

実体がない / 根拠に乏しい / 説得力に欠ける / 物足りない、実質が伴わない

Her argument sounded insubstantial when the professor asked for evidence.

教授が証拠を求めたとき、彼女の主張は実体に欠けているように聞こえた。

Sense（1）

Lacking substance; not real or strong.

The bridge was insubstantial and would not safely carry a car.

more insubstantial

（ comparative ）

most insubstantial

（ superlative ）