monogamist

/məˈnɑɡəmɪst/
noun
  1. A person who practices or advocates monogamy, the custom of being married to or having a sexual relationship with only one person at a time.
    • The speaker, a committed monogamist, argued that monogamy strengthens family bonds.
    • He described himself as a monogamist and was not interested in open relationships.
    • As a monogamist, she believed in building a life with one partner.
Antonyms
What does "monogamist" mean? | whatsthatwordmean | whatsthatwordmean