po‧lyg‧a‧my (n) /pəˈlɪgəmi/ [puh-lig-uh-mee]
     1. The practice or condition of having more than one spouse, esp. wife, at one time. (Also called plural marriage.) Commonly used to refer to the practice whereby one man is married to two or more women.
     2. Zoology. The habit or system of mating with more than one individual, either simultaneously or successively.

po‧lyg‧y‧ny (n) /pəˈlɪdʒəni/ [puh-lij-uh-nee]
     1. The practice or condition of having more than one wife at one time.
     2. (Among male animals) The habit or system of having two or more mates, either simultaneously or successively.