The compound adjective 'well-lighted' is a straightforward combination of two native English elements. The adverb 'well', with its ancient Proto-Germanic root wel, conveys the sense of sufficiency or proper condition. It is paired with 'lighted', the adjectival form derived from the Old English verb for illuminating. The term's logic is transparently descriptive, directly stating that a space is illuminated to a satisfactory or ample degree. This compound follows a common Germanic pattern for creating descriptive adjectives, such as 'well-known' or 'well-behaved', where 'well-' modifies a participial adjective to indicate a positive quality. Its evolution is purely within English, without the need for borrowing, reflecting a practical approach to describing the desirable state of a physical environment.

Structure: well (adequately) + lighted (illuminated) - well: From Old English wel, meaning 'in a good manner, satisfactorily'. In this compound, it functions as an intensifying adverb meaning 'adequately' or 'properly'. - lighted: From Old English līhtan, līehtan, meaning 'to shine, give light'. It is the past participle form of the verb 'light', functioning here as an adjective meaning 'illuminated'.