Best move is better than excellent move. Though, there is a brilliant move (I never got it in any of my games ) which is better than best move. The way I understand it, brilliant move is assessed as better than "best" move after it is played. It probably has something to do with the depth in which you conclude the analysis, though I am really not sure how it is determined as brilliant precisely.
Brilliant move isn't "better" than the best move it IS the best move. It is just trickier to spot than most moves and usually involves a sacrifice
Best is better