Being very important, or key to something.
Having or containing the centre of something.
Being in the centre.
Exerting its action towards the peripheral organs.
centre
Serious, high-level; significant
Of or pertaining to a major sports league; belonging to the professional level of a sport, such as US baseball.
Analogous in importance to a major league sports team.
An association of sports teams which plays at the highest skill level of its sport, especially Major League Baseball.
The highest level of competition in a field of endeavor.