1.
to firmly believe, to be convinced, to be under the impression
To believe something completely without doubt, often regardless of whether it is actually true.
彼女は噂を信じ込んでいる。
She firmly believes the rumor.
自分が正しいと信じ込んでいた。
I was convinced that I was right.
詐欺師の話を信じ込んでお金を騙し取られた。
I believed the scammer's story completely and was cheated out of money.
信じ込む is a compound verb with ～込む adding the sense of thoroughness or completion.
TRANSITIVITY:
- Type: 他動詞 (transitive)
- Pattern: Xを信じ込む / Xと信じ込む
ASPECT (ている):
- 信じ込んでいる: is firmly convinced (state)
NUANCE:
Often implies blind or possibly mistaken belief. More emphatic than 信じる alone.
COMPOSITION:
- 信じる: to believe
- ～込む: suffix adding completeness/thoroughness