a technical musician is someone who mainly focusses on his technique rather than on everything else. these dudes are known for their ability to play the most difficult stuff flawlessly.
its the technical aspect of playing. finger movenemt.

a theoretical musician is someone who focusses mainly on music theory and makes it his holy grail. everything they write is perfectly bound to music theory and he´ll be able to dissect every work by any composer and tell you exaclty whats going on. they analyze every frigging chord. a common problem among those players is, that alot of them lack the ability to improvise spontaneously over any given progression by just trusting their ear - simply because they never concerned themselves with it.

a good musician is a (more or less) technical player who has (not necessarily) some basic knowledge of music theory but refuses to comply himself to anything but his ear and heart.