congeries vs summation

congeries and summation both are nouns.

Word	Noun	Adjective	Verb	Adverb
congeries	Yes	No	No	No
summation	Yes	No	No	No

As nouns, summation is a hypernym of congeries; that is, summation is a word with a broader meaning than congeries:

Other hypernyms of congeries include sum, sum total.

congeries (noun)	summation (noun)
a sum total of many heterogenous things taken together	the arithmetic operation of summing; calculating the sum of two or more numbers
	a concluding summary (as in presenting a case before a law court)
	the final aggregate
	(physiology) the process whereby multiple stimuli can produce a response (in a muscle or nerve or other part) that one stimulus alone does not produce