Spacemonkey is the nickname of Daniel Jackson, given by Jack O'Neill. Daniel hates said name, which makes Jack use it even more. Given to him after he is alive after all (he almost pulled a Daniel Jackson).
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.