N-COUNT 多余物;累赘 If you describe something such as a building, addition, or development as an excrescence, you strongly disapprove of it because you think it is unnecessary, bad, or ugly. 多余物;累赘 [literary, disapproval]
...an architectural excrescence.
多余的建筑物
The trade union block vote is an excrescence on democracy. [+ on]