The Greek word for "repent" is "metanoia" (noun) and "matanoeo" (verb) you see as defined in the Strongs #3340, 3341: to think differently or afterwards, reconsider. After thought, change of mind. Repentance basically means a "change of mind" and the context must determine what is involved in this change of mind. Where salvation is in view, repentance unto salvation actually precedes saving faith in Christ and is not a totally separate act from faith. It is actually the same coin with two sides. Repentance is on one side, what you change your mind about and faith in Christ is on the positive side, the new direction of this change of mind. *Repentance and faith are two sides of the same experience of being brought to Christ.
The Bible also tells us that true repentance will result in a change of actions. Acts 26:20 declares, "I preached that they should repent and turn to God and prove their repentance by their deeds." This is the fruit of repentance (Matthew 3:8), not the essence of repentance. I have heard certain people say, "If you want to be saved, repent of your sins, turn from your sins." If turning from your sins means to stop sinning, then people can only be saved if they stop sinning. And it is unlikely that anyone has ever been saved, since we don't know anyone who has ever completely stopped sinning.