Ask a stupid question...

Reading through an old Supreme Court case written by Chief Justice Vinson today, I came across the word "minuend" in a footnote. Eagerly taking this chance to expand my vocabulary, I went to Merriam Webster online, where I found this definition:

Main Entry: min·u·end
Pronunciation: 'min-y&-"wend
Function: noun
Etymology: Latin minuendum, neuter of minuendus, gerundive of minuere to lessen -- more at MINOR
: a number from which the subtrahend is to be subtracted.
(My emphasis--D.)

So, now I thought, double-banger--I'm going to learn two words today. So what did Merriam Webster have to say about 'subtrahend', you ask?

Main Entry: sub·tra·hend
Pronunciation: 's&b-tr&-"hend
Function: noun
Etymology: Latin subtrahendus, gerundive of subtrahere
: a number that is to be subtracted from a minuend.

Welcome to law school!!