Discipleship

Luke 9:1 says "Jesus called together His twelve apostles and gave them complete power over all demons and diseases.." Which is how it reads in the bible version I'm reading right now. I was wondering if the original Greek word used here was "apostle" or "disciple" (because to me apostle means teacher and disciple means follower and student). It wasn't that easy however! For starting with the Greek concordance, I looked up "apostle" and found it was not used in Luke 9:1, but when I looked up "disciple" I found that wasn't used either(!) What was written originally was "And having called together the twelve he gave them power and authority over all the demons and diseases to heal.." (from the "Interlinear NASB-NIV Parallel New Testament in Greek and English"). I then thought to myself that "the twelve" is likely closer to "apostle" then "disciple". It's important because I presently know three people battling stage four cancers.
- All in all, I decided, I will continue my prayers and encouragement to them, because "apostle" or "disciple" Jesus said many times things like "what ever things you desire, when you pray, believe you have them and you shall have them.." and "where two or more agree in prayer as touching anything upon earth, my Father in heaven will hear them and give it to them.." (Well, these are paraphrased from my memory.. which is faulty at best and getting worse as I get older! But you get my drift I hope..)
- However, and in addition, when I went back to the concordance (Strong's Exhaustive) I found that apostle means "messenger" and "sent out"(one).. (And "disciple" is "learner, instructed one".)