This paper examines the Arabic origins of the common word root fork and its related derivatives like forchette, bifurcate as well as related words like diverge, diverse, adverse, averse, divorce, divert, avert, fragmentation, fraction in English, German, French, Latin, Greek, Russian, and Sanskrit from a consonantal radical or lexical root theory perspective. More precisely, the data consists of three sets of 30 such words as shall be seen below. Despite their different spellings and forms, they all share a common, core meaning of 'separation, division, and opposition'. The results clearly show that all such related words have true Arabic cognates, with the same or similar forms and meanings whose different forms, however, are all found to be due to natural and plausible causes and different courses of linguistic change. Furthermore, they show the failure of English and European historical lexicography and linguistics in manifesting the close genetic relationships between Arabic and such languages. As a consequence, the results indicate, contrary to traditional Comparative Method and Family-Tree Model claims, that Arabic, English, and all the so-called Indo-European languages belong to the same language, let alone the same family. Therefore, they prove the adequacy of the consonantal radical theory in relating Indo-European languages to Arabic as their origin all because, unlike any other language in the group, it has cognates in common with all of their branches.