The state of being acquainted; knowledge or familiarity with someone or something obtained through meeting or experience.
From acquaintance with the variant suffix -cy (Latin -cia), which creates abstract nouns denoting states or conditions. Similar to how 'fraudulent' becomes 'fraudulency,' -cy changes adjectives and nouns into abstract state nouns.
Acquaintancy is an older, more formal word for what we'd usually call 'acquaintance' today—you'll see it in historical literature and legal documents where writers were more likely to use formal variants like this!
Complete word intelligence in one call. Free tier — 50 lookups/day.