What does 違いない mean?
違いない is a Japanese noun meaning “(phrase) sure, no mistaking it, for certain” in English. It is written as 違いない in kanji, ちがいない in hiragana, and chigainai in romaji. This word is part of JLPT N3 vocabulary.
Example sentence
再婚した今、彼はもっと幸福に違いない。
He must be happier now after having remarried.