n.

1. 模仿，模拟；仿造；伪造[U]
   I learned the song by imitation.

   我通过模仿学会了这支歌。

2. 仿制品；赝品[C]
   The vase is an imitation of the one in the museum.

   这只花瓶是博物馆那只的仿制品。

a.

1. 人造的；仿制的；伪造的
   The man was wearing an imitation leather jacket.

   这人穿着一件人造革皮夹克。

n.

1. the action of imitating.
2. a copy of an authentic article.
3. Music  the repetition of a phrase or melody in another part or voice, usually at a different pitch.