To stand out from the class or rank (e. g. to ask question).

A Dictionary of Chinese Buddhist Terms, William Edward Soothill and Lewis Hodous

===（雜語）禪客，出於眾而問話曰出陣，終曰入陣，蓋取法戰之義也。楊岐會和尚錄曰：「一日七人新到。師問：陣勢既圓，作家戰將何不出陣與楊岐相見？」

丁福保《佛學大辭典》