The literal term 'Space Marine' is not as common as I thought, which isn't really that surpsising because if virtually all your marines operate in space, do you

The literal term 'Space Marine' is not as common as I thought, which isn't really that surpsising because if virtually all your marines operate in space, do you really need to add it to their name? However, I do believe that space marine is the most common generic term to refer to soldiers-in-space ooc (ie when discussing the archetype and not specific implementations like Heinlein's 'Mobile Infantry' - keep in mind there are actual space marines in some of his other stories, Alien's 'Colonial Marines' or Starcraft's 'Confederate Marines').