Top 4 Definitions of  Amigo (a friend):      (from Dictionary.com)

amigo  (-mg)

1. A person whom one knows, likes, and trusts.

2. A person whom one knows; an acquaintance.

3. A person with whom one is allied in a struggle or cause; a comrade.

4. One who supports, sympathizes with, or patronizes a group, cause, or movement: friends of the clean air movement