The adjective indeterminable describes something that can't be known for sure, like what grade you would’ve gotten on a paper you never turned in.

To determine is to calculate something, make a final decision, or to be sure. Something that's indeterminable is none of these — it’s not able to be determined. Maybe you need more information or better math skills. The grade you would’ve gotten on a paper you didn’t write is indeterminable, but if you’re lucky your teacher will give you an extension. Then that shining “C” is all yours!

Definitions of indeterminable
  1. adjective
    not capable of being definitely decided or ascertained
    synonyms: undeterminable
    not capable of being computed or enumerated
    not capable of being determined
    unascertainable, undiscoverable
    not able to be ascertained; resisting discovery
    unknown in advance
    indeterminate, undetermined
    not precisely determined or established; not fixed or known in advance
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    capable of being determined or limited or fixed
    capable of being calculated or estimated
    ascertainable, discoverable
    capable of being ascertained or found out
    capable of being defined, limited, or explained
    capable of being judged or decided
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  2. adjective
    incapable of being definitely ascertained
    not capable of being computed or enumerated
Commonly confused words

indeterminate / indeterminable

Understanding the nuances of this word pair, indeterminate and indeterminable, hinges on understanding the words' parts. The root word, determine, means to establish something.

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Word Family

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