Strong's 2250 (ἡμέρα)

age, + alway, (mid-)day (by day, (-ly)), + for ever, judgment, (day) time, while, years

day, i.e. (literally) the time space between dawn and dark, or the whole 24 hours (but several days were usually reckoned by the Jews as inclusive of the parts of both extremes); figuratively, a period (always defined more or less clearly by the context)

feminine (with G5610 (ὥρα) implied) of a derivative of (to sit; akin to the base of G1476 (ἑδραῖος)) meaning tame, i.e. gentle;