みいとこ

Meanings

1

noun

third cousin

usually written using kana alone

Refers to a third cousin: the child of one's parent's second cousin, or the grandchild of a great-grandparent's sibling.

younger brother, faithful service to elders

いとこ
いとこ means 'cousin' (first cousin). みいとこ is a more distant relative, specifically a third cousin.
はとこ
はとこ means 'second cousin'. みいとこ is one generation further removed.

Compound of 三 (mi, 'three') and 従兄弟 (itoko, 'cousin'), literally 'third cousin'. The reading みいとこ is a contraction of み (mi) and いとこ (itoko).