Something uncertain: the uncertainties of modern life.
Statistics The estimated amount or percentage by which an observed or calculated value may differ from the true value.
synonyms:
uncertainty, doubt, dubiety, skepticism, suspicion, mistrust These nouns refer to the condition of being unsure about someone or something. Uncertainty, the least forceful, merely denotes a lack of assurance or conviction: I regarded my decision with growing uncertainty. Doubt and dubiety imply a questioning state of mind: “Doubt is part of all religion” (Isaac Bashevis Singer) On this point there can be no dubiety. Skepticism generally suggests an instinctive or habitual tendency to question and demand proof: “A wise skepticism is the first attribute of a good critic” (James Russell Lowell) Suspicion is doubt as to the innocence, truth, integrity, honesty, or soundness of someone or something: His furtiveness aroused my suspicions. Mistrust denotes lack of trust or confidence, as in a person's motives, arising from suspicion: The staff viewed the consultant's hasty recommendations with mistrust.
The American Heritage® Dictionary of the English Language, Fourth Edition