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esposo (Noun) "spouse"
12th cent. From Latin sponsus 'id.,' the past participle of spondere "to pledge," "to promise (for another)." From Proto-Italic *spond-eje/o- "to pledge," probably older "to offer (in ceremony)." From Proto-Indo-European *spond-ei̯e/o- "to libate." From earlier *spond- 'id.'
Romance: Western Vulgar Latin: Asturian esposu, Portuguese esposo, Galician esposo, Catalan espòs, French époux, Italian sposo; Sardinian: sposu
Italic: Umbrian spefa "offering"
Indo-European: Hellenic: Ancient Greek σπονδή (spondé) "libation;" Tocharian: B spänt- "to trust;" Anatolian: Hittite išpānt-i "to libate"