What is Yesteryear?
1.
Years ago, not last year, as you would assume from the meaning of 'yesterday'. it's much more general. Middle English, not really in use nowadays.
I think back to my golden memories of yesteryear...
2.
A word meaning last year.
Yester can also be put in front of other words.
Ex. Yesteryear
Yestermonth
Yesterday
Yestertime
Yesterhour
etc.
Remember yesteryear, when we burned the inside of that garbage can?
See