1A hill — a natural rise of ground that's gentle and not as high as a mountain; a knoll.
公園の丘の上でピクニックをした。
We had a picnic on top of the hill in the park.
丘の向こうに海が見える。
You can see the sea beyond the hill.
その村は丘に囲まれた静かな場所にある。
That village lies in a quiet spot surrounded by hills.
2In mahjong (as a scoring term), a bonus number of points added to the top-place finisher's score at the end of a game, on top of the difference from the starting point total. Usually written in katakana as オカ.
このルールでは、オカは一位に一万点プラスされる。
Under this rule, the oka adds 10,000 points to whoever finishes first.
半荘が終わったので、丘を含めて最終得点を計算した。
Now that the game was over, we calculated the final scores including the oka.