ascendancy
noun [ U ] formal (also ascendency) uk/əˈsen.dən.si/ us/əˈsen.dən.si/
权势显赫，处尊居显；优势，支配地位
a position of power, strength, or success
They are in danger of losing their political ascendancy (= controlling power). 他们的政治权位岌岌可危。
Supporters of the proposal are currently in the ascendancy over its opponents (= are more powerful than them). 提案的支持者目前占据上风（压倒了反对者）。