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vinculum matrimonii

American  
[wing-koo-loom mah-tri-moh-ni-ee, ving-kyuh-luhm ma-tri-moh-nee-ahy] / ˈwɪŋ kʊˌlʊm ˌmɑ trɪˈmoʊ nɪˌi, ˈvɪŋ kyə ləm ˌmæ trɪˈmoʊ niˌaɪ /

noun

Latin.
  1. the bond of matrimony.