Learning science is like learning another language. If you are learning to speak another language like Chinese or Japanese – WHAT WOULD YOU DO?
It is the same procedure while you are learning science. My advise is – use the word more often. How would you use the word more often though?
Well, everybody has different ways and methods. You could build your own table of glossary per each topic in science or make a memory card (front page with the definition and back page with the term), or even write the word many times. Some psychologists say that humans learn words by saying it or by forgetting the word few times. This is why teachers make you to do different activities and ask you to get involved into the discussion in the class.
Probably, the best way to learn science language is by ENJOYING IT! 
So, don’t bore yourself. Move on to something else if you can’t really learn the word -because you can alway come back to it.