The state or quality of lasting, continuing, or remaining in effect; the characteristic of continuance.
From continuance plus the suffix -cy (Latin -cia), creating abstract nouns. The -cy suffix is used similarly to -ness, often with a more formal or technical register.
Continuancy is a word you'll find in insurance documents and legal contracts—it's the boring but crucial quality of 'staying in force.' Without continuancy, every policy would need constant renewal.
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