adjective/biˈkonkabo/
biconcave
Etymology tree Proto-Indo-European *dwóh₁ Proto-Indo-European *dwi- Proto-Italic *dwi- Latin bi-der. Proto-Indo-European *dwóh₁ Proto-Indo-European *dwís Proto-Italic *dwis Old Latin duis Latin bisder. Spanish bi- Proto-Indo-European *ḱe? Proto-Indo-European *ḱóm Proto-Italic *kom Proto-Italic *kom- Latin con- Proto-Indo-European *ḱewh₁-der. Proto-Indo-European *ḱowh₁ós? Proto-Italic *kawos Latin cavus Latin concavusbor. Spanish cóncavo Spanish bicóncavo From bi- + cóncavo.