noun, noun, used as a suffix, noun which may take the genitive case particle 'no'
the end of; last time doing; finishing up
Used as a suffix after a noun or the -masu stem of a verb to mean the final instance of that action or the end of a period. Often seen in set expressions like 仕事納め (last workday of the year) or 稽古納め (last practice session).
今日は今年の仕事納めだ。
Today is the last workday of the year.
明日が稽古納めなので、しっかり練習しよう。
Tomorrow is the last practice, so let's train hard.
終わり is a general noun for 'end' or 'finish', while 納め specifically implies the final instance of a recurring activity or the end of a period, often with a sense of completion or wrapping up.
Derived from the verb 納める (おさめる, 'to put away, finish, conclude'), used as a nominalized suffix. The kanji 納 carries the sense of storing or settling something, fitting the idea of a final, conclusive instance.