The compound noun "walk-through" is a modern formation from the phrasal verb "to walk through," meaning to explain or rehearse something step by step. The literal image is of guiding someone through a process as if physically leading them from start to finish. The element "walk" evolved from Old English verbs connoting motion, while "through" has maintained its core Germanic sense of penetration or completion. The term's logic lies in this metaphorical extension: just as one walks through a physical space, one is verbally guided through a sequence of instructions or a virtual environment, emphasizing thoroughness and clarity.

Structure: walk (to move on foot) + through (from one side to the other) walk: From Old English wealcan (to roll, toss) and wealcian (to roll up, curl), of Germanic origin. In this compound, it functions as a verb-derived element meaning "to proceed or go." through: From Old English þurh, of Germanic origin, related to Dutch door and German durch. It functions as a preposition/adverb meaning "from one end or side to the other," indicating a complete traversal.