either member of a married pair in relation to the other; one's husband or wife.
–verb (used with object)
2.
Obsolete. to join, give, or take in marriage.
Origin: 1150–1200; (n.) ME < OF spous (masc.), spouse (fem.) (aph. for espous, espouse) < L spōnsus,spōnsa lit., pledged (man, woman) (n. uses of ptp. of spondēre to pledge), equiv. to spond- verb s. + -tus, -ta ptp. suffix; (v.) ME spousen < OF esp(o)user;cf. espouse
c.1200, "a married woman in relation to her husband" (also of men), from O.Fr. spus (fem. spuse), from L. sponsus "bridegroom" (fem. sponsa "bride"), from masc. and fem. pp. of spondere "to bind oneself, promise solemnly," from PIE *spend- "to make an offering, perform a rite" (see spondee). Spouse-breach (c.1225) was an old name for "adultery."
[n. spous, spouz; v. spouz, spous] 
noun, verb, spoused, spous⋅ing.