What does 一昨日 mean?
一昨日 is a Japanese noun meaning “the day before yesterday” in English. It is written as 一昨日 in kanji, おととい in hiragana, and ototoi in romaji. This word is part of JLPT N5 vocabulary.
Example sentence
「ウィキペディアを引用するな」という主張が昨日だか一昨日だかの朝日新聞に載っていた。
The exhortation "Don't quote Wikipedia" was included in the Asahi newspaper of yesterday or the day before.