Insubstantial is an adjective that means lacking form, substance or nutritional value. If you're really hungry, a bowl of clear broth will seem pretty insubstantial.
If there is insubstantial evidence to convict an accused criminal, he will be set free. In the office, insubstantial expenses should be paid out of the petty cash draw. A thin blouse is too insubstantial to be worn in this cold weather. And a candy bar makes an insubstantial lunch — a sandwich and fruit would be more nutritious.
