noun
parallel cousins; ortho-cousins
Anthropological term for children of a parent's same-sex sibling (e.g., father's brother's children or mother's sister's children). Contrasts with 交叉いとこ (cross cousins).
父の弟の子供は、私にとって平行いとこにあたる。
My father's younger brother's children are my parallel cousins.
平行いとこと交叉
The distinction between parallel cousins and cross cousins is important in the study of kinship structures.