The quality or state of being full of chance, risk, and uncertainty; the characteristic of depending on luck and fortune.
From chanceful + -ness (Old English suffix -ness meaning state or condition). The -ness suffix has been productive since Old English for creating abstract nouns.
Notice how 'chancefulness' takes a simple concept—luck—and wraps it in multiple suffixes until it becomes almost abstract and philosophical; English does this constantly, turning concrete experiences into abstract philosophical states.
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