partner
/ˈpɐːtnə/noun
The person someone shares a romantic relationship or home life with, such as a spouse.
Also a business co-owner; a modifier like 'law partner' or 'life partner' settles which is meant.
Related words
guardianA person who protects or watches over someone or something.divorceThe official ending of a marriage by law.orphanA child whose parents have died, or (less commonly) who has lost one parent.weddingThe ceremony at which two people are married.twinOne of two children (or animals) carried in the same womb at the same time and born at the same birth.marriageA formal union between people that makes them family and brings legal, social, or religious rights and duties.