From Middle English wallopen (“gallop”), from Anglo-Norman, from Old Northern French walop (“gallop (noun)”) and waloper (“to gallop (verb)”) (compare Old French galoper, whence modern French galoper), from Frankish *wala hlaupan (“to run well”) from *wala (“well”) + *hlaupan (“to run”), from Proto-Germanic *hlaupaną (“to run, leap, spring”), from Proto-Indo-European *klaup-, *klaub- (“to spring, stumble”). Possibly also derived from a deverbal of Frankish walhlaup (“battle run”) from *wal (“battlefield”) from a Proto-Germanic word meaning "dead, victim, slain" from Proto-Indo-European *wel- (“death in battle, killed in battle”) + *hlaup (“course, track”) from *hlaupan (“to run”). Compare the doublet gallop.
wallop (plural wallops)
- A heavy blow, punch.
- A person's ability to throw such punches.
- An emotional impact, psychological force.
- A thrill, emotionally excited reaction.
- (slang) anything produced by a process that involves boiling; Beer, tea, whitewash.
- (archaic) A thick piece of fat.
- (UK, Scotland, dialect) A quick rolling movement; a gallop.
- (beer): codswallop
- (intransitive) To rush hastily
- (intransitive) To flounder, wallow
- (intransitive) To boil noisily
- (transitive) To strike heavily, thrash soundly.
- (transitive) To trounce, beat by a wide margin.
- (transitive) To wrap up temporarily.
- Webster's Seventh New Collegiate Dictionary, Springfield, Massachusetts, G.&C. Merriam Co., 1967