Bible Greek and Hebrew Dictionaries combined for Word Studies
Genesis Chapter 1
day 3637 # oktaemeros {ok-tah-ay'-mer-os}; from 3638 and 2250; an eight-day old person or act: -- the eighth {day}.
eighth 3590 # ogdoos {og'-do-os}; from 3638; the eighth: -- {eighth}. eighth 3637 # oktaemeros {ok-tah-ay'-mer-os}; from 3638 and 2250; an eight-day old person or act: -- the {eighth} day.
eighth 8083 ## sh@moneh {shem-o-neh'}; or sh@mowneh {shem-o-neh'}; feminine sh@monah {shem-o-naw'}; or sh@mownah {shem-o-naw'}; apparently from 8082 through the idea of plumpness; a cardinal number, eight (as if a surplus above the "perfect" seven); also (as ordinal) eighth: -- eight([-een, -eenth]), {eighth}.
the 3637 # oktaemeros {ok-tah-ay'-mer-os}; from 3638 and 2250; an eight-day old person or act: -- {the} eighth day.