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Definitions

insoluble

[in-sol-yuh-buhl] / ɪnˈsɒl yə bəl /
ADJECTIVE
mysterious, unable to be solved or answered
Synonyms
WEAK
baffling difficult impenetrable indecipherable inexplicable inextricable irresolvable mystifying obscure unaccountable unconcluded unfathomable unresolved unsolvable unsolved
Antonyms
WEAK
explainable explicable obvious open solvable

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

For example, if your daily goal is 30 grams of fiber, about 20 grams should come from insoluble fiber and 10 grams from soluble fiber.

From Science Daily • Mar. 8, 2026

Soluble fiber dissolves in water and slows digestion, while insoluble fiber helps move waste through the digestive tract.

From Science Daily • Mar. 8, 2026

Purple, savoy and green cabbage are also high in insoluble fiber, which Beitchman says is “the broom of the digestive system,” allowing waste to pass through more easily.

From Salon • Feb. 21, 2026

It’s the counterpoint to Syd’s earliest argument for sticking with this insoluble endeavor: “Why can’t we put everything that we have into everything that we can?”

From Salon • Jun. 26, 2025

More than the question of compensation, then, the relocation problem was perilously close to insoluble.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis