This basketball team has been a powerhouse in the league for many years.

powerhouse 是由 power（力量）和 house（房屋、场所）组成的复合词，字面意思是"力量的场所"。在体育领域引申为"实力强大的队伍"或"常胜队伍"，形容长期保持竞争优势的团队。