adverb / noun
yesterday
YES-ter-day/ˈjestərdeɪ/
The day before today.
The picnic was rainy yesterday, but today's calendar leaf shows sunshine.

Etymology
The compound pairs a word already meaning “yesterday” with “day,” explicitly naming the day immediately before today. Other Germanic languages often use their equivalent of the first element alone.
In context
something I'm realizing today is that yesterday was mentally exhausting being able to follow a trail I can just kind of turn my brain off let my mind wander whereas yesterday I had to be switched on the entire time
More examples
- The package arrived yesterday.
- Yesterday was the busiest day of the week.
- I finished the report yesterday afternoon.
Forms
yesterday