1590s, as a term in logic, "unqualified, asserting absolutely," from Late Latin categoricus, from Greek kategorikos "accusatory, affirmative, categorical," from kategoria (see category). General sense of "explicit, unconditional" is from 1610s. Categorical imperative, from the philosophy of Kant, first recorded 1827. Related: Categorically.
a categorical denial
catechism
catechist
catechize
catecholamine
catechumen
categorical
categorization
categorize
category
catenary
cater