SPOUSE is a 6 letter word that starts with S.

1. \Spouse\, n. [OF. espous, espos, fem. espouse, F.
   ['e]poux, ['e]pouse, fr. L. sponsus, sponsa, prop. p. p. of
   spondere, sponsum, to promise solemnly, to engage one's self.
   Cf. {Despond}, {Espouse}, {respond}, {Sponsor}.]
   1. A man or woman engaged or joined in wedlock; a married
      person, husband or wife.
   
            At last such grace I found, and means I wrought,
            That that lady to my spouse had won.  --Spenser.
   
   2. A married man, in distinct from a spousess or married
      woman; a bridegroom or husband. [Obs.]
   
            At which marriage was [were] no person present but
            the spouse, the spousess, the Duchess of Bedford her
            mother, the priest, two gentlewomen, and a young
            man.                                  --Fabyan.
   
   

2. \Spouse\, v. t. [See {Espouse}, and Spouse, n.]
   To wed; to espouse. [Obs.]
   
         This markis hath her spoused with a ring. --Chaucer.
   
         Though spoused, yet wanting wedlock's solemnize.
                                                  --Spenser.
   
         She was found again, and spoused to Marinell.
                                                  --Spenser.
   
   

(Cant. 4:8-12; Hos. 4:13, 14) may denote either husband or wife, but in the Scriptures it denotes only the latter.