four-week

The compound adjective "four-week" is a modern English formation built from two ancient, foundational elements. The numeral "four" traces back to the Proto-Indo-European root kʷetwóres, which gave rise to the number across many Indo-European languages, signifying a specific quantity. The term "week" originates from a Germanic root concerning sequence or change, evolving to denote a standard seven-day cycle. Combined with a hyphen, these morphemes create a transparent, descriptive term where the quantifier "four" directly modifies the temporal unit "week" to specify a duration, illustrating English's productive capacity for forming precise compound modifiers.

Structure: four (number) + week (time period) - four: From Old English fēower, of Proto-Germanic origin; related to Dutch vier and German vier, from an Indo-European root shared by Latin quattuor and Greek tessares. Functions as a numerical quantifier. - week: From Old English wice, wicu, of Proto-Germanic origin; related to Dutch week and German Woche, from a base probably meaning "a turning" or "succession". Functions as the noun denoting the unit of time being measured.