三人

From Old Japanese.

• The most likely derivation is from 三 (mi, “3, three”) +‎ 人 (-tari, counter for persons).

(Can this⁽⁺⁾ etymology be sourced?)

• Today, "三人" is commonly read as "さんにん", uncommonly as "みたり".

三(み)人(たり) • (mitari) 

1. three person; three people

• 一人(ひとり) (hitori, “one person”)
• 二人(ふたり) (futari, “two people”)
• 四人(よたり) (yotari, “four people”)
• 五人(いつたり) (itsutari, “five people”)
• 六人(むたり) (mutari, “six people”)
• 十人(とたり) (totari, “ten people”)

三(さん)人(にん) • (sannin) 

1. three person; three people

   二人(ふたり)より三人(さんにん)がいい。

   Futari yori sannin ga ī.

   Three persons are better than two persons.

• 三人寄れば文殊の知恵