day, daylight, daytime

evening, late-night hour, lights-out, midnight, small hours

daytime, dusk, predawn, daylight, summertime, wintertime, moonlight, moonlit, sunrise, moonless, noontime, stargazing, nightlong, springtime, evenings, nightfall, night, midsummer, diurnal, sundown, midwinter, candlelight, mornings, daybreak, sunset, noonday, skies, midnight, woodcocks, weekends, afternoons, catnaps, owling, sleep, darkness, bedtime, outdoors, bivouacs, nrem sleep, lovebug, flashlight, mealtime, nightlight, neap tide, illumination, weekday, respites, strobe, alpenglow, noctilucent, hourlong, frequency, luna moth, hummingbird moth, stroboscopic, summer, firefly, naps, polysomnogram, nightscape, dawn, moonrise, sun, weeknight, winter, hours, indoors, vehicular, wakefulness, starlight, air, strobe lighting, strobe light, lights, dapples, nighthawks, dimness, reveille, sleepyheads, aerial, twilight, landings, penlight, torchlight, nonstop, klieg, mugginess, routine, snowy, trailside, sunlight, starlit, suppertime, naptime, sulphurs, monthlong, day, dinnertime, celestial, overcast, noons, brightness, fie, low, seawater, autumn, blues, deep, incubation, monday, outside, pre, read, saturday, sitting, weekend, \u00bb, autumnal, call, nocturnal, lnitial, ambient, hourly, postprandial, prescribed, suboptimal, baseline, forecasted, peak, prandial, pretreatment, submaximal, suprathreshold, admissible, fluctuating

wedding night, weeknight

day, mean solar day, solar day, twenty-four hours

amount of time, period, period of time, time period

dark, night, nightly, nocturnal