Where does “Katharevousa” come from?

Katharevousa (English) comes from Greek καθαρεύουσα, from Ancient Greek καθαρεύω, from Ancient Greek -εύω, from Ancient Greek -εύς — Added to noun or adjective stems to form a...

Katharevousa (English): A learned, archaising form of Modern Greek, based on Classical Greek and used for formal and official purposes; it was legally displaced as the official language of Greece in 1976 by Demotic Greek

Definitions

A learned, archaising form of Modern Greek, based on Classical Greek and used for formal and official purposes; it was legally displaced as the official language of Greece in 1976 by Demotic Greek

Ancestry of “Katharevousa”, step by step

Step	Language	Word	Meaning
1	Greek	καθαρεύουσα	Katharevousa
2	Ancient Greek	καθαρεύω	to be clean, pure; to be pure
3	Ancient Greek	-εύω	Added to the stems of agent or other nouns in...
4	Ancient Greek	-εύς	Added to noun or adjective stems to form a...

Every word from Ancient Greek -εύς →Every word from Ancient Greek -εύω →Every word from Ancient Greek καθαρεύω →