Q: I’m seeing the verbs “rifle” and “riffle” used interchangeably. I’d use “rifle” (pronounced like the weapon) for searching through a box for something, and riffle” (to my mind, beautifully onomatopoeic) for going through papers. Are these still two distinct terms?
A: Yes, the verbs “rifle” and “riffle” are still two distinct terms, but they overlap somewhat, and it’s not surprising that some people confuse them.
Both verbs can refer to searching, but “rifle” suggests a search for something to steal, while “riffle” means flipping through pages, perhaps searching for something and perhaps not.
(“Rifle” here is pronounced, as you say, like the firearm, while “riffle” rhymes with “piffle.”)
The verb “rifle” is by far the older of the two terms. English borrowed it in the 14th century from Anglo-Norman and Old French, where rifler meant to scratch, scrape, graze, or plunder.
When the verb entered English in the late 1300s, it meant to carry off as booty, to plunder or rob, to ransack or search a receptacle for valuables to steal, and several other felonious actions, according to the Oxford English Dictionary.
The first example cited is from Confessio Amantis (circa 1391), a Middle English poem by John Gower: “He ruyfleþ [rifleth] bothe book and belle.”
And here’s an example from Piers Plowman (c. 1378), an allegorical poem by William Langland: “I roos whan þei were areste and riflede hire males” (“I rose when they were at rest and rifled their bags”).
Piers Plowman is also the source of this OED citation: “What wey ich wynde ful wel he aspieþ, / To robbe me and to ryfle me” (“He clearly discovers which path I take, / To rob me and to rifle me”).
When the verb “riffle” showed up in the 18th century, it referred to storm damage, specifically the stripping of slate, tiles, and other roof coverings.
Oxford says it’s of unknown origin, but may be a variant or alteration of the verbs “rifle,” “ruffle,” or “ripple.” (Remember, the French sources of “rifle” meant to scratch or scrape, as well as to plunder.)
In the dictionary’s earliest citation, from a poem in a 1713 issue of the Monitor, a storm does its damage at sea: “A sudden Storm descends, / That, in an Instant, riffles all the Boat, / Whose scatter’d Streamers on the Billows float.”
In the 19th century, the OED says, “riffle” took on the sense you’re asking about: “To flick through (papers, books, etc.); to thumb (a block of paper, a book, etc.), releasing the leaves in (usually rapid) succession.”
The earliest citation is from Johnson’s New Universal Cyclopedia (1878): “Every three minutes the book is taken out of its covers and ‘riffled.’ Riffling consists in shaking up the leaves, so as to loosen the whole and prevent the gold from clinging to the parchment.”
Here’s a more recent example, minus the gold, from Stephen King’s On Writing: A Memoir of the Craft (2000): “Most magazine editors can tell how long a story is just by looking at the print and riffling the pages.”
As for the use of the verbs “rifle” and “riffle” today, here are the relevant definitions from Oxford Dictionaries online (a different entity from the OED):
rifle: “Search through something in a hurried way in order to find or steal something: ‘she rifled through the cassette tapes.’ ”
riffle: “Turn over something, especially the pages of a book, quickly and casually: ‘he riffled through the pages.’ ”
You didn’t mention the felonious implications of the verb “rifle” in your question, but we should note that all six of the standard dictionaries we’ve consulted mention stealing as the goal of rifling.
Finally, the noun “rifle” (the firearm) doesn’t come from the verb “rifle” (to search for loot). However, the noun is derived from another verb “rifle” (to cut spiral grooves inside the barrel of a firearm). And both of those verbs may share a French ancestor, rifler (to scratch or to plunder).
from Grammarphobia http://www.grammarphobia.com/blog/2016/09/rifle-riffle.html