In a manner that is sociable, friendly, and characteristic of club members getting along together.
From 'clubby' (adjective) plus the adverbial suffix '-ly,' which converts adjectives into adverbs describing how something is done.
When a group behaves 'clubbily,' they're bonding hard—inside jokes, shared references, and an almost exclusive atmosphere that makes outsiders feel left out, whether intentionally or not.
Complete word intelligence in one call. Free tier — 50 lookups/day.