Weightlessness is a space word. It begins with the letter w.
Terra Firma (If that's what you mean by space word)
Weightlessness and zero gravity are space words. They begin with the letters w and z.
Woozy
One possibility is the word genesis.
A w-word is a euphemism for any avoidable word beginning with W.
· weightlessness
widow
Weightlessness is a space word. It begins with the letter w.
wigwam
Terra Firma (If that's what you mean by space word)
Wise
Within
waistwaitwalletwarrantwasn'twartwentweren'twhatwheatwitwicketwombatwon'tworst
Weightlessness and zero gravity are space words. They begin with the letters w and z.
widow
Weep