varietism

Noun

obsolete uncountable

(obsolete) The practice of nonmonogamy.

Japanese Meaning

非一夫一婦制の実践 / 一夫一婦制以外の恋愛または結婚関係の実践

The historian argued that varietism, though rarely acknowledged, shaped family structures in the coastal towns.

その歴史家は、ほとんど認められていなかった非一夫一婦制の慣行が沿岸の町々の家族構造を形作ったと主張した。

Sense（1）

(obsolete) The practice of nonmonogamy.

"Sexual varietism" is a more neutral term for those who relate sexually to several partners.