godan verb (-su), transitive verb
leave a message; tell someone before leaving; state in one's will
Used when you tell someone something before you go, or when you leave instructions or a final message, including in a will.
彼は家族に遺言を言い残した。
He left a will for his family.
出かける前に、妻に「すぐ戻る」
Before going out, I told my wife, 'I'll be right back.'
godan verb (-su), transitive verb
leave unsaid; forget to mention
Used when you intentionally or unintentionally do not say something that should have been said.
大事なことを言い残してしまった。
I forgot to mention something important.
彼は不満を言い残したまま去った。
He left without saying what he was dissatisfied about.