eighth

The word 'eighth' is a transparent ordinal formation built directly upon the cardinal number 'eight'. The root 'eight' descends from the Proto-Germanic ahtōu, which itself originates from the Proto-Indo-European oḱtṓw, the ancient and stable numeral for the quantity. The suffix '-th' is a productive ordinal marker in English, inherited from its Germanic ancestry, specifically from Proto-Germanic -dô. The combination follows a perfectly regular pattern: the cardinal number provides the quantitative value, and the suffix transforms it into a term denoting sequential position or rank. Thus, the literal construction "eight-th" logically means "number eight in a series" or "one of an eight-part division."

Structure: eight (number) + th (ordinal suffix) - eight: From Old English eahta, of Germanic origin; related to Dutch acht and German acht, from an Indo-European root shared by Latin octo and Greek oktō. Functions as the cardinal number base. - th: A suffix of Germanic origin, used to form ordinal numbers from cardinal numbers (e.g., fourth, fifth, sixth). It denotes position in a series.