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adj. Too apparent to be doubted; unquestionable.

adj. clearly true; providing no possibility of doubt.

n. That which is indubitable.

adj. Not dubitable or doubtful; too evident to admit of doubt; unquestionable; evident; apparently certain.

Not dubitable; too plain to admit of doubt: as, indubitable proof.

Synonyms See list under indisputable.

adj. too obvious to be doubted

"There must have been certain indubitable evidences by which a communication from heaven could be distinguished."

unquestionable   

indubitably   

irrefragable    evident    incontrovertible    undeniable    incontestable    unquestionable    undoubtable   

incontrovertible    unquestionable    indisputable    undeniable    unimpeachable    corroborative    unequivocal    unquestioned    conclusive    self-evident