Literally: new – old – replace – apologize
Alternately: Replacing the old with the new. Originally this yojijikugo referred to living organisms expelling waste and taking in new resources; but by extension it has also come to mean renewal and reform in a society or organization… something we desperately need right now.
Notes: Despite the literal meanings of the characters, 代謝 as a compound means renewal; changing one thing out for another; regeneration; or even metabolism, of all things. As in, “basal metabolic rate” is 基礎代謝率 (kiso taisha ritsu).
代 is sometimes read as dai, but in the context of this compound, that’s considered an error.