All Night
Sleepless Night, All Nighter
noun, verbal noun, の adjective
Penetrate the night and go on through to the morning. You were up all night and had a sleepless night, aka an all nighter.
This is a jukugo word that uses the on'yomi readings of the kanji. You've seen these before, although 夜 can be a little tricky. It's the same や reading as in 今夜 and 深夜. Here's a mnemonic just in case:
You spend all night watching the Yankees (や). You should probably be sleeping, or at least doing your reviews or something, but instead you spend a sleepless night watching Yankees baseball games. Are the Yankees really that interesting?
英語を徹夜で勉強するなんて、いかにもあの子らしいよね。
It’s just like her to study English all night.