noun which may take the genitive case particle 'no', noun
after an all-nighter; morning after staying up all night
Describes the state or time after having stayed awake all night, often implying tiredness or a groggy feeling. Commonly used as a noun or with の to modify another noun.
My head is fuzzy after staying up all night.
An exam after an all-nighter is tough.
Compound of 徹夜 (all-night, staying up all night) and 明け (dawn, end of a period).