n.

1. 【天】【测】子午线，经线[C]
   Every place on the same meridian has the same longitude.

   同一经线上的地方其经度相同。

2. （太阳等天体对地面而言的）最高点[the S]
3. 顶点；全盛期[the S]
   He was at the meridian of his power then.

   那时他获得了最高权力。

a.

1. 顶点的；全盛期的
   meridian fame

   最高名誉

2. 【天】【测】子午线的，经线的
   the meridian circle

   子午环

3. （太阳等天体对地面而言的）最高点的
   the meridian hour

   正午时刻

n.

1. a circle of constant longitude passing through a given place on the earth's surface and the poles.
   ▸Astronomy  a circle passing through the celestial poles and the zenith of a given place on the earth's surface.
2. (in acupuncture and Chinese medicine) a pathway in the body along which vital energy is said to flow.