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one's time (e.g. to go on stage); one's turn
source; origin; place of production
「出場」 has another reading with different meanings.
彼女の出場が大会を盛り上げた。
Her appearance livened up the tournament.
やっと自分の出場の番が来た。
My turn to go on finally came.
次の選手の出場を待っています。
We're waiting for the next player's entry.