This is the 7707th most frequent Chinese word.
過環
"過環" does not seem to be a standard Chinese term. It might be a typo, specialized jargon, or an uncommon phrase.
Here, 過環 is used as a noun to name the specific game.
過環是中國古代的一種投環遊戲。
Guohuan is an ancient Chinese ring-toss game.
In this context, 過環 refers to the activity related to the game.
他在公園裡參與了一場過環比賽。
He participated in a ring-toss competition in the park.
Here, 過環 identifies the type of toy for the specified game.