The quality of being considerable; the state of being large, significant, or important enough to be worth noticing.
Considerable (from Latin considerare 'to examine carefully') + -ness noun suffix. Both considerableness and considerability emerged in English to express the abstract quality of significance.
Both considerableness and considerability mean almost the same thing, showing how English loves to build multiple pathways to express the same idea—linguistic redundancy is actually a feature!
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