Synonyms of the word 
UNEXPLAINED → INCOMPREHENSIBLE - INEXPLICABLE - UNDETERMINED
unexplained
- adj. Not explained. Of unknown cause or origin.
incomprehensible
- adj. Impossible or very difficult to understand.
inexplicable
- adj. Impossible to explain; not easily accounted for.
undetermined
- adj. Not determined; not settled; not decided.
- adj. Not limited; not defined; indeterminate.
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