Middle Of The Night, Late At Night
noun
The deep night is the middle of the night. It doesn't get any deeper than that before you start coming out of the night to start the next day.
しんや
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
こんな深夜に、どうしたの?
What's up this late at night?
ここは深夜にお酒と音楽を楽しめるバーです。
This is a bar where you can enjoy music and alcohol until late at night.
深夜に電話できる友人は何人くらいいますか?
How many friends do you have that you can call even at midnight?