also: すみ
This document has been checked.
Please give me a receipt showing payment has been made.
This is a document that has already been verified.
済む is the conjugating verb meaning 'to be finished/settled', whereas 済み is its noun/suffix form attached directly to nouns like 確認済み.
Standard suffix form; the reading ずみ is used when attached to a noun.
Rare standalone reading; the suffix is normally read ずみ.
Irregular okurigana usage; less common than 済み.
Derived from the verb 済む (すむ, 'to finish, be settled'), with the suffix form undergoing rendaku to ずみ.
built-in; predefined