The word 'underlayer' is a transparent Modern English compound formed from two native Germanic elements. The prefix 'under,' from Old English under, has a stable history tracing back to Proto-Germanic under- and Proto-Indo-European ndher-, meaning "below." The noun 'layer' emerged in the 14th century from the Middle English verb leyen (to lay), which itself descends from Old English lecgan. The compound's logic is perfectly literal: an "under-layer" is simply a stratum placed beneath another. Over time, this concrete meaning was extended metaphorically to describe individuals in subordinate social or organizational strata, maintaining the core concept of being positioned below something else.

Structure: under (beneath) + layer (stratum) under: Old English origin, meaning "beneath, below, among." It functions as a prefix indicating lower position or rank. layer: Middle English origin, from the verb "lay," meaning "a single thickness or stratum of material." It functions as the root noun.