おととい一昨日ototoiおとつい一昨日ototsuiいっさくじつ一昨日issakujitsu
1.

A reference to the day that comes immediately before yesterday, indicating a specific time two days ago from the current day.

2.

A more formal or refined expression denoting the period of time that elapsed two days prior to today, often used in written or formal contexts.

3.

A colloquial term predominantly used in western Japan to describe the day that precedes yesterday, showcasing regional linguistic variations.

4.

An expression that can be used in a dismissive context, implying that someone should not return since their last visit was the day before yesterday.

Example:

「ウィキペディアを引用するな」という主張が昨日だかだかの朝日新聞に載っていた。