the verb 'walk' originates from old english 'wealcan', meaning "to roll, toss, or move about", and its causative form 'wealcian', "to roll up, curl". these derive from proto-germanic walkaną, "to roll". the semantic shift from "rolling" to "walking" likely occurred in middle english, influenced by the similar-sounding old norse verb 'valka', meaning "to wander". the modern sense of moving on foot at a moderate pace became established, with '-ing' forming the present participle, adjective, and gerund noun. thus, 'walking' connects an ancient concept of circular or aimless motion to the specific, purposeful human locomotion we know today.

the word 'walking' is a present participle or gerund form derived from the verb 'walk'. it is not productively segmented into separate morphemes in modern english spelling without altering the base form.