ADJ
（人、观点、行为）主流的，传统的，约定俗成的
You can use mainline to describe people, ideas, and activities that belong to the most central, conventional, and normal part of a tradition, institution, or business.
例句
We observe a striking shift away from a labor theory among all mainline economists...
我们发现在主流经济学家中间出现了一种偏离劳动理论的显著变化。
Mainline feminism was arguing for the inherent beauty of the natural woman.
主流女权主义思想倡导女性天生的自然美。