Denomination and Denominator

Denomination and Denominator.  It seems like these two words would be related, and yet one definition is about religious groups and currency.  The other is about dividing in mathematics/arithmetic, shared traits and average levels.  And then denominate is about giving a name to something.  There must be a history site for word origins, so let me know if you are aware of one.  Today we're looking at the brilliant foliage in a pear orchard at the top of Mountain Street in Grimsby.