every night; nightly
Indicates that something happens each night, often as a regular occurrence. Can be used as a noun or adverbially.
Looking at the stars every night is my daily routine.
彼は夜ごと遅くまで働いている。
He works late every night.
every day and every night; day after day; daily
Standard modern spelling using ごと for the suffix.
Kanji spelling using 毎; less common but still seen.
Compound of 夜 (yo, 'night') and the suffix ごと (goto, 'every'). The suffix ごと attaches to nouns to mean 'each' or 'every'.