Meaning of 境界線 in Japanese

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Definition of 境界線

きょうかいせん(kyoukaisen) 【境界線】

(n) boundary line
ここで明確にしなければならない点は、スポーツにおいてアマチュアとプロフェッショナルの境界線が消失しつつあるということだ。
The point we must clarify here is that the lines between amateur and professional in sport are beginning to disappear.

ぐんじきょうかいせん(gunjikyoukaisen) 【軍事境界線】

The point we must clarify here is that the lines between amateur and professional in sport are beginning to disappear.