particle
and; such things as
Listing particle for non-exhaustive examples, often tied to a specific time and place. Softer than と.
机の上に本やペンがある。
There are books, pens, and such on the desk.
particle
as soon as; the minute ...
Follows the dictionary form of a verb; often in the pattern や否や. Literary or formal.
See also: や否や
彼は家に着くや否や、電話をかけた。
He called as soon as he got home.
copula
Kansai dialect copula, equivalent to だ. Casual and regional.
See also: だ
これ、めっちゃうまいやん。
This is really good, isn't it? (Kansai)
interjection
Punctuational exclamation in haiku, renga, etc. Poetic and traditional.
古池や蛙飛びこむ水の音
The old pond—a frog jumps in, the sound of water. (Bashō)
interjection
Archaic interjection or question particle. No longer used in modern Japanese.
「や、さようにござります」と古い文に書いてある。
In old texts, you see things like 'Yes, that is so.'