Where does “키릴문자” come from?

키릴문자 (Korean) comes from Korean 키릴, from Russian Кири́лл, from Ancient Greek Κύριλλος, from Ancient Greek κῡ́ριος — main; major; primary; principal.

키릴문자 (Korean): a Cyrillic character, Cyrillic alphabet

Definitions

키릴문자 traces back through two separate lines of ancestry.

Step	Language	Word	Meaning
1	Korean	키릴	Kirill, Kiril a Slavic male name
2	Russian	Кири́лл	Saint Cyril apostle to the Slavs and inventor of the Glagolitic alphabet, which served as the basis for the Cyrillic alphabet
3	Ancient Greek	Κύριλλος	—
4	Ancient Greek	κῡ́ριος	main; major; primary; principal

Step	Language	Word	Meaning
1	Korean	문자	letter, character, alphabet; phrase, passage;...