see-through

The compound adjective "see-through" is a modern English formation, following a transparent and literal compounding pattern. The verb "see" originates from the Proto-Germanic sehwaną, itself from the Proto-Indo-European root sekʷ- meaning "to see, to follow." The preposition/adverb "through" derives from Proto-Germanic thurh, related to the PIE root terə- meaning "to cross over, pass through." The logic of the compound is entirely literal, describing a property where vision can pass through a material from one side to the other. This concrete meaning later extended metaphorically to describe ideas or deceptions that are so insubstantial they offer no visual or intellectual barrier to understanding their true nature.

Structure: see (perceive with eyes) + through (from one side to the other) - see: From Old English sēon, meaning "to perceive with the eyes, look, behold." Its functional role is the verb root meaning "to perceive visually." - through: From Old English þurh, meaning "from one side to the other, by means of." Its functional role is a preposition/adverb indicating penetration or passage.