six-week-old

the compound adjective 'six-week-old' is a modern english formation built entirely from germanic elements. 'six' originates from the proto-germanic sehs, a direct cognate of latin 'sex' and greek 'hex', all descending from the proto-indo-european root swéḱs. 'week' derives from proto-germanic wikōn, likely related to the concept of a sequence or change. 'old' stems from proto-germanic aldaz, from the pie root h₂el- meaning 'to grow, nourish'. the compound's logic is transparent and arithmetic: it sequentially specifies a quantity of time units ('six weeks') and then attributes the state of having existed for that duration ('old'), resulting in a precise descriptor for age.

Structure: six (number) + week (time unit) + old (age) six: from old english 'siex', of germanic origin; functions as a cardinal number. week: from old english 'wice', of germanic origin; functions as a noun denoting a period of seven days. old: from old english 'eald', of germanic origin; functions as an adjective describing age or duration.