Roget's Thesaurus of English Words and Phrases by Peter Mark Roget

adj.; dubiety, dubitation†, dubitancy†, dubitousness†. hesitation, suspense; perplexity, embarrassment, dilemma, bewilderment; timidity &c (fear) 860; vacillation &c 605; diaporesis†, indetermination. vagueness &c adj.; haze, fog; obscurity &c (darkness) 421; ambiguity &c (double meaning) 520; contingency, dependence, dependency, double contingency, possibility upon a possibility; open question &c (question) 461; onus probandi [Lat.]; blind bargain, pig in a poke, leap in the dark, something or other; needle in a haystack, needle in a bottle of hay; roving commission. precariousness &c adj.; fallibility. V. be uncertain &c adj.; wonder whether. lose the clue, lose the clew, scent; miss one's way. not know what to make of &c (unintelligibility) 519, not know which way to turn, not know whether one stands on one s head or one's heels; float in a sea of doubt, hesitate, flounder; lose oneself, lose one's head; muddle one's brains. render uncertain &c adj.; put out, pose, puzzle, perplex, embarrass; confuse, confound; bewilder, bother, molder, addle the wits, throw off the scent, ambiguas in vulgus spargere voces [Lat.]; keep in suspense. doubt &c (disbelieve) 485; hang in the balance, tremble in the balance; depend. Adj. uncertain; casual; random &c (aimless) 621; changeable &c 149. doubtful, dubious; indecisive; unsettled, undecided, undetermined; in suspense, open to discussion; controvertible; in question &c (inquiry) 461. vague; indeterminate, indefinite; ambiguous, equivocal; undefined, undefinable; confused &c (indistinct) 447; mystic, oracular; dazed. perplexing &c v.; enigmatic, paradoxical, apocryphal, problematical, hypothetical; experimental &c 463. unpredictable, unforeseeable (unknowable) 519. fallible, questionable, precarious, slippery, ticklish, debatable, disputable; unreliable, untrustworthy. contingent, contingent on, dependent on; subject to; dependent on circumstances; occasional; provisional. unauthentic, unauthenticated, unauthoritative; unascertained, unconfirmed; undemonstrated; untold, uncounted. in a state of uncertainty, in a cloud, in a maze; bushed, off the track; ignorant, &c 491; afraid to say; out of one's reckoning, astray, adrift; at sea, at fault, at a loss, at one's wit's end, at a nonplus; puzzled &c v.; lost, abroad, désorienté; distracted, distraught. Adv. pendente lite [Lat.]; sub spe rati [Lat.]. Phr. Heaven knows; who can tell? who shall decide when doctors disagree? ambiguas in vulgum spargere voces [Lat.]. SECTION IV. REASONING PROCESSES