Conceivably

adv. [f. as prec. + -LY².] In a conceivable manner: as may be imagined or supposed; imaginably, possibly.

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1625. Bp. Mountagu, App. Caesar, 61. The first thing he … possibly and conceiveably could doe.

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1646. Sir T. Browne, Pseud. Ep., I. i. 4. Being truth it selfe [he cannot] conceiveably admit the impossible society of error.

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1841. Myers, Cath. Th., III. § 9. 33. The testimony of the best men … may conceivably not be trustworthy.

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