Neologisms in Papers

I'm writing my Anthropology paper and I keep making up words that Microsoft Word doesn't recognize. They include:

• gravitic: relating to gravity. "This causes a gravitic problem."
• civilizational: of a civilization. "a civilizational breakdown" (recognized by Webster)
  
• naturality: relating to nature. "realize the naturality of the situation" (recognized by Webster)

I don't know where "gravitic" came from, most likely Star Trek.