insoluble

Let a bottle of salad dressing stand on the table for a few hours and you will notice that it has separated into layers. That's because oil is insoluble or is not capable of being dissolved.

Insoluble comes from the Latin insolubilis meaning "that cannot be loosened." When a substance is insoluble, it cannot be dissolved or loosened in water. Similarly, a situation that is insoluble has no hope of being solved. When a marriage is beyond repair and cannot be fixed, it is insoluble.

Definitions of insoluble
  1. adjective
    (of a substance) incapable of being dissolved
    synonyms: indissoluble
    non-water-soluble, water-insoluble
    not soluble in water
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    Antonyms:
    soluble
    (of a substance) capable of being dissolved in some solvent (usually water)
    alcohol-soluble
    soluble in alcohol
    dissoluble, dissolvable
    capable of dissolving
    fat-soluble
    soluble in fats
    disintegrable, meltable
    capable of melting
    oil-soluble
    soluble in oil
    water-soluble
    soluble in water
    show more antonyms...
  2. adjective
    admitting of no solution or explanation
    “an insoluble doubt”
    Synonyms:
    incomprehensible, inexplicable
    incapable of being explained or accounted for
    insolvable, unresolvable, unsoluble, unsolvable
    not easily solved
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    Antonyms:
    soluble
    susceptible of solution or of being solved or explained
    explicable
    capable of being explicated or accounted for
    answerable
    capable of being answered
    resolvable, solvable
    capable of being solved
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  3. adjective
    without hope of solution
    “an insoluble problem”
    Synonyms:
    hopeless
    without hope because there seems to be no possibility of comfort or success
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