early-morning hour(n = noun.time) - an hour early in the morning;
is a kind of hour, time of day
is a part of forenoon, morn, morning, morning time

by the hour, canonical hour, credit hour, eleventh hour, happy hour, hour, hour angle, hour circle, hour hand, kilometers per hour, kilometres per hour, kilowatt hour, late-night hour, light hour, man hour, miles per hour, person hour, rush hour, semester hour, sidereal hour, twenty-four hour period, witching hour, zero hour