Living being that has zero parents, zero grandparents, zero great-grandparents and five great-great-grandparents in common with other living beings.
irregular-triple-third-cousin.
Someone who, in relation to others, has zero parents, zero grandparents, zero great-grandparents, zero great-great-grandparents and seventeen great-great-great-grandparents in common.
Irregular-nonuple-fourth-cousin.