numeration vs reckoning

numeration and reckoning both are nouns.

Word	Noun	Adjective	Verb	Adverb
numeration	Yes	No	No	No
reckoning	Yes	No	No	No

As nouns, numeration and reckoning are synonyms defined as:

numeration and reckoning: the act of counting; reciting numbers in ascending order

Other synonyms of numeration include count, counting, enumeration, tally.

numeration (noun)	reckoning (noun)
the act of counting; reciting numbers in ascending order	the act of counting; reciting numbers in ascending order
naming numbers	problem solving that involves numbers or quantities
	a bill for an amount due