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relaxed; familiar; easy to access; friendly
新しい部長は気安い態度だ。
The new manager has a relaxed manner.
彼は誰とでも気安く話せる人だ。
He's someone who can talk familiarly with anyone.
パーティーの雰囲気はとても気安かったので、皆が楽しめた。
The atmosphere at the party was so easy-going that everyone enjoyed themselves.