The state or quality of being applicable or relevant; the extent to which something applies to a situation.
From applicable (capable of being applied) + -ancy (noun suffix forming abstract nouns). Applicable comes from Latin applicabilis (capable of being attached).
Applicancy is one of those abstract legal and philosophical words—a lawyer might argue about the 'applicancy of precedent' to a new case, which basically means how much an old law applies to a new situation.
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