n.

1. 【天】【測】子午線，經線[C]
   Every place on the same meridian has the same longitude.

   同一經線上的地方其經度相同。

2. （太陽等天體對地面而言的）最高點[the S]
3. 頂點；全盛期[the S]
   He was at the meridian of his power then.

   那時他獲得了最高權力。

a.

1. 頂點的；全盛期的
   meridian fame

   最高名譽

2. 【天】【測】子午線的，經線的
   the meridian circle

   子午環

3. （太陽等天體對地面而言的）最高點的
   the meridian hour

   正午時刻

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.