wallop

A severe and powerful blow, which may be either dealt or received. I got a really nasty wallop from a two-by-four on the construction site last week. His left hook can deal a nasty wallop if he catches you with it.

An interjection used for emphasis, especially to indicate loud noises. I was falling asleep on the couch when that framed photo fell off the wall and shattered, crash bang wallop!

Fig. to provide a burst of energy, power, or excitement. Wow, this spicy food really packs a wallop. I put a special kind of gasoline in my car because I thought it would pack a punch. It didn't.

Also, pack a wallop.

COMMON If something packs a punch, it has a very powerful effect. He is known for designing clothes that really pack a punch. The advert packs a punch with its straightforward, real, no-tricks approach. Note: People also sometimes say that something packs a wallop. Many years after it was made, this movie still packs a wallop.

To exert formidable power. In modern English to wallop means to thrash, and in noun form, a heavy blow, but originally the verb meant to boil with a noisy, bubbling sound, and the noun also was slang for ale. Glyndebourne, site of a summer opera festival in England, perpetuates the last meaning in the name of its restaurant, Nether Wallop (Lower Ale). The verb pack in this expression means “to deliver.” The term dates from the early twentieth century. Eugene O’Neill used it literally in his play The Hairy Ape (1922): “He packa da wallop, I tella you.” Figuratively it appears in such locutions as, “The candidate’s speech really packed a punch.”