Extreme dangerousness.

Roget 665: danger, peril, insecurity, jeopardy, risk, hazard, venture, precariousness, slipperiness; instability etc. 149; defenselessness etc. adj., exposure etc. (liability) 177; vulnerability; vulnerable point, heel of Achilles^†; forlorn hope etc. (hopelessness) 859.    [Dangerous course] leap in the dark etc. (rashness) 863; road to ruin, faciles descensus Averni [Lat.] [Vergil], hairbreadth escape.    cause for alarm; source of danger etc. 667.    rock ahead [Approach of danger], breakers ahead; storm brewing; clouds in the horizon, clouds gathering; warning etc. 668; alarm etc. 669.    [Sense of danger] apprehension etc. 860.    ... show more

Being unsettled or in doubt or dependent on chance:
— The precariousness of his income.

synonyms: uncertainness, uncertainty.

Roget 475: uncertainty, incertitude, doubt; doubtfulness etc. adj.; dubiety, dubitation^†, dubitancy^†, dubitousness^†.    hesitation, suspense; perplexity, embarrassment, dilemma, bewilderment; timidity etc. (fear) 860; vacillation etc. 605; diaporesis^†, indetermination.    vagueness etc. adj.; haze, fog; obscurity etc. (darkness) 421; ambiguity etc. (double meaning) 520; contingency, dependence, dependency, double contingency, possibility upon a possibility; open question etc. (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 etc. adj.; fallibility.    ... show more

Dutch: onzekerheid, twijfel