Where does “Wall” come from?

Wall comes from Old English wælisc, which originally referred to something foreign or non-Germanic in origin.

Ancestry of “Wall”, step by step

Step	Language	Word	Meaning
1	Middle English	wall	Alternative form of wale
2	Old English	weall	wall; fervour; uproar; boiled or mulled wine
3	Proto-Germanic	wallaz	well, spring; wall, rampart, entrenchment
4	Latin	vallum	wall, rampart, entrenchment
5	Proto-Indo-European	wēl-	—