Capaciousness: A word I cannot live up to...

Since retiring from teaching, I have become a student of the Supreme Court.  I am receiving a fairly comprehensive education in many respects.

I have to look up the definition of words not generally used in everyday conversations. As such, I have to look up "capacious" every time I hear/read it, which is quite often in the language of the Supreme Court.  

Given one of the general uses of the term, I get the irony of having to look it up every time:

"High Capacity: Emphasizes the ability to contain or retain more than average, rather than just having a large area"