Strong's Number 8064

Strong's Concordance - Hebrew #H8064

שָׁמַיִם shamayim {shaw-mah'-yim} The second form being dual of an unused singular; from an unused root meaning to be lofty; the sky (as aloft; the dual perhaps alluding to the visible arch in which the clouds move, as well as to the higher ether where the celestial bodies revolve).

Strong's Hebrew Bible Dictionary