A concatenation of "yesterday," "today" and "tomorrow," indicating a specific period of time where it's so late that it's technically the next day (past midnight) but in your head it's still "today" even though you're discussing (technically) yesterday.
Guy: I remember discussing it yestdayrow with Charlotte.
Girl: Which yestdayrow?
Guy: The one that just passed...
Girl: Ohh...
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