early 15c., numeracioun, "method or process of numbering or calculating," from Latin numerationem (nominative numeratio) "a counting out, paying, payment," noun of action from past-participle stem of numerare "to count, number," from numerus "number" (see number (n.)). Meaning "act or process of counting the number of" is from mid-15c.
numen
numerable
numeracy
numeral
numerate
numeration
numerative
numerator
numerical
numerology
numerosity