If one group has ascendancy over another group, it has more power or influence than the other group.
例句
Although geographically linked, the two provinces have long fought for political ascendancy...盡管在地理上彼此依存，兩省卻長期為獲取政治支配權你爭我奪。The extremists are gaining ascendancy.極端分子正逐漸占據上風。
英漢詞典釋義
n.
優勢；支配地位
We have had ascendancy over the enemy in the battle.在戰斗中我們已占有優勢。
英英詞典釋義
Noun
1. the state that exists when one person or group has power over another;
"her apparent dominance of her husband was really her attempt to make him pay attention to her"