filius nullius
noun | \ ˈfi-lē-əs-ˈnə-lē-əs, -nə-ˈlī-əs; ˈfē-lē-u̇s-ˈnu̇-lē-u̇s \ | fi·li·us nul·li·us
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: an illegitimate child : bastard — called also filius populi