n.

1. 伸長；延長[U]
   As I sat in a shadowy corner, I observed a slow and gradual elongation of his mouth.

   坐在一個暗角落裡我觀察到他的嘴慢慢而逐漸地伸長。

2. 延長部分[C]
   The dotted lines indicate the elongation.

   虛線表示延長的部分。

n.

1. the lengthening of something.
2. Astronomy  the angular separation of a planet from the sun or of a satellite from a planet.