Well there is best friends,close friends, good friends, bad friends, weird friends, cool friends, mean friends and so on and so forth. But there is the friend that is closer than you own family, that's the best one. But i don't know what you are looking for. ._.
The study of the history of words and their meanings
Answer:
It most likely means a reminder that your past is still there and will not ever be truly gone
The alien was able to defy the laws of gravity.
Hope this helped! (: