nighttime

Từ điển WordNet v3.1 - WordNet Dictionary

noun

the time after sunset and before sunrise while it is dark outside (Freq. 1)
• Syn:
night, dark
• Ant:
day (for: night)
• Derivationally related forms:
nightly (for: night)
• Hypernyms:
time period, period of time, period
• Hyponyms:
weeknight, wedding night
• Part Holonyms:
day, twenty-four hours, twenty-four hour period, 24-hour interval, solar day, mean solar day
• Part Meronyms:
evening, late-night hour, midnight, small hours, lights-out