뒷북

뒤 (dwi, “back; late”) +‎ ㅅ (-s-, genitive interfix) +‎ 북 (buk, “drum”), literally "late drum"; usually used with 치다 (chida, “to beat”).

• (SK Standard/Seoul) IPA^(key): [tɥit̚p͈uk̚] ~ [tɥip͈uk̚] ~ [tyt̚p͈uk̚] ~ [typ͈uk̚]
• Phonetic hangul: [뒫뿍/뒤뿍]

뒷북 • (dwitbuk)

1. doing or saying something after the fact; doing or saying something after the appropriate time for it has passed

   뒷북인 거 아는데 축하한다.

   Dwitbugin geo aneunde chukhahanda.

   I know it's overdue, but congratulations.

2. (Internet slang) reposting

• 뒷북치다 (dwitbukchida, “to do or say something after the appropriate time for it has passed”)

• 소 잃고 외양간 고친다 (so ilko oeyanggan gochinda, “one fixes the cow barn after losing the cow”, proverb)