smooth
Verbsmooths, smoothing, smoothed
Formssmooths, smoothing, smoothed
Pluralsmooths
- 1Having a surface or texture that lacks roughness and offers little friction.
The river stones had been worn smooth by centuries of flowing water.
A freshly sanded board feels remarkably smooth.
Similareven, level, polished, sleek, silky
Oppositerough, uneven, bumpy, coarse
Note
The physical sense the others grow from. Middle English smothe comes from Old English smēþe and smōþ, a West Germanic word of unknown origin with relatives in Scots smuith and Dutch smeuïg. Touch is the test: Dryden's 1695 translation of du Fresnoy's De Arte Graphica wants outlines "imperceptible to the touch, and even." Rough is the everyday opposite, and "smooth of surface" is a natural phrase.
- 2Proceeding without difficulty, problems, or unexpected setbacks.
The merger went through after surprisingly smooth negotiations.
A well-rehearsed crew kept the launch smooth from start to finish.
Similareasy, seamless, effortless, trouble-free
- 3To make a surface even and free of roughness or irregularities.
Workers smooth the wet concrete before it dries.
She smoothed the bedsheet until no wrinkles remained.
Similarsmoothen
Oppositeroughen, wrinkle, crumple, rumple
Note
The everyday transitive verb, which always takes an object: you smooth a skirt, a sheet or wet concrete. William Gibson's The Miracle Worker (1961) has "She smooths her skirt." The forms are smooths, smoothed and smoothing, with no added e. Smoothen is a synonym, but the plain verb does the same work.
- 4To make a process straightforward or free of obstacles.
Mediators worked hard to smooth the tense negotiations between the two sides.
Her experience smoothed the company's transition to new software.
Similarease, facilitate
Oppositehinder, complicate, obstruct, impede
- 5Flowing or spoken without interruption or harshness; fluent and pleasant to hear.
The narrator's smooth phrasing held the audience through the whole chapter.
A jazz saxophonist drew out one long, smooth line of melody.
Similarflowing, fluent, fluid, mellifluous
Oppositehalting, choppy, jerky, harsh
Note
Once a term of praise in literary criticism, given to verse that runs without a jolt. Milton uses it in 1670 for "the only smooth poet of those times." Pope's imitation of Horace (1737) shows its limits: "Waller was smooth; but Dryden taught to join / The varying verse." Smoothness is a virtue there, but a lesser one than power. In Gay's The Fan (1713), it belongs to speech, where smooth elocution flows.
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- 8Lacking projections, indentations, or serrations along an edge or surface.
Botanists noted the plant's smooth leaf margins, with no teeth at all.
The coin's smooth rim distinguished it from the milled coins of the era.
Oppositeserrated, toothed, jagged
Note
An edge word, used wherever a tooth or notch would be the alternative. Knives come with a smooth blade or a serrated one. Botanists describe a leaf with a smooth margin, and Robert E. Swanson's field guide to Southern Appalachian trees and shrubs (1994) gives the technical name for such a margin: entire. Here the natural opposite is serrated, not rough.
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- 14Of muscle tissue, lacking striations and operating involuntarily.
Smooth muscle in the gut moves food along without conscious effort.
Blood vessels rely on smooth muscle to widen and narrow.
Oppositestriated
Note
Anatomy sorts muscle by how it looks under the microscope. Smooth muscle lacks the stripes, or striations, of the muscle we move at will. Its fibers are spindle-shaped and work under involuntary control in the walls of hollow organs such as the intestines, blood vessels and bladder. The word nearly always appears in the fixed phrase smooth muscle.
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- 16Suave and persuasive in manner, often in a way that feels glib or insincere.
Her smooth reassurances did little to calm the worried investors.
He was far too smooth a talker to be believed.
Similarglib, slick, suave, silky
Note
The darker side of polish: words that slide past objection without earning trust. Addison's Cato (1713) warns that "smooth discourse and mild behavior oft / Conceal a traitor," and smooth explanations or smooth reassurances carry the same suspicion. Context sets the tone. When the charm is admired rather than doubted, the word has moved to the "suave" meaning.
- 17Evenly and without difficulty or interruption.
The car handles smooth on the open highway.
The plan went smooth from start to finish.
Note
A flat adverb: the bare adjective doing the work of smoothly. It survives mainly in set phrases like run smooth and the saying about true love never running smooth. It also appears in compounds such as smooth-running, smooth-tongued and smooth-spoken. Shakespeare's "Smooth runs the water where the brook is deep" (Henry VI, Part 2) puts it first for effect. Outside such phrases, smoothly is the safer choice.
- 18Anything even or untroubled, especially a stretch or phase that proceeds easily.
A seasoned manager learns to take the rough with the smooth.
After miles of broken pavement, the cyclists reached a welcome smooth.
Oppositerough
Note
The noun lives mostly in a pairing: take the rough with the smooth, accepting good stretches and bad together. Thackeray writes of "the roughs and the smooths of this daily existence," and Anne Manning (1860) of roughs and smooths set against one another. An older, concrete use survives in the King James Bible of 1611: "the smooth of his neck."
- 19An instance of smoothing; a single stroke or pass that flattens or evens a surface.
With a quick smooth of her skirt, she stood to greet them.
He gave the bedsheet a final smooth and left the room.
- 20Of a function, having derivatives of all orders at every point in its domain.
A smooth function can be differentiated again and again without limit.
Physicists assume the field is smooth so its higher derivatives all exist.
Note
Analysts call this class C^∞: every derivative exists, and so does the next one, all of them continuous. It sits above functions that are merely differentiable and just below analytic ones. As Eric W. Weisstein's CRC Concise Encyclopedia of Mathematics (2003) puts it, any analytic function is smooth, but a smooth function is not necessarily analytic.
- 21To process data so the meaningful patterns stand out while random noise is removed.
Statisticians smooth noisy measurements before plotting the seasonal trend.
The algorithm smoothed the image, softening grain without blurring edges.
Note
The same operation runs through statistics, image processing and digital audio: keep the signal and drop the jitter. Much depends on how wide the averaging window is. Murray R. Spiegel and Larry J. Stephens's Schaum's Outline (1999) finds 7-month moving averages smoothing their series better than 3-month ones. The data is the object, smoothing names the process, and the result is a smooth.
- 22Of a sound, produced without marked aspiration, in Greek, taking the smooth breathing rather than the rough.
A smooth breathing over the initial vowel signals the absence of an h-sound.
Editors restored the smooth mark that earlier scribes had omitted.
Oppositerough
Note
Greek grammar's word for a vowel spoken without an h-sound before it. The smooth breathing, or spiritus lenis, is set against the rough breathing that marks /h/. The difference has consequences in the language itself: Benjamin Franklin Fisk's Greek grammar of 1830 notes that οὐ becomes οὐκ before a smooth vowel and οὐχ before an aspirate. In this pairing, rough means aspirated and smooth means not.
- 23Of an integer, factoring completely into small prime numbers.
A number is smooth when all its prime factors are small.
Factoring algorithms run fastest on smooth integers.
Note
Number theorists attach a bound to it. A B-smooth number has no prime factor larger than B, so "small" always means small relative to a chosen limit. The idea does real work in sieve-based factoring and discrete-logarithm algorithms, which hunt for smooth values because they break apart so readily into known primes.
- 24The result produced by a smoothing procedure: a cleaned estimate of the underlying pattern in data.
The analyst overlaid the smooth on the scatter of original points.
Each smooth captured the seasonal cycle more clearly than the raw series.
Note
Statisticians turn the procedure into a countable noun. The curve or series a smoothing method produces is a smooth, as in Wolfgang Härdle's "a smooth of the potato data set" (1990). It is the fitted output: the systematic part of the data once noise is suppressed by kernels, splines or moving averages. The process itself belongs to the data-smoothing verb.
- 25A domestic animal, especially a dog or cat, bred with a short, sleek coat.
Among the litter, only one smooth had the short, glossy coat.
She prefers a smooth because the fur needs little grooming.
Note
A breeder's and fancier's noun, clipped from smooth-coated and used where a variety also comes with a rough coat. The two nouns pair off as types. William Ernest Castle and Sewall Wright's Studies of Inheritance in Guinea-pigs and Rats (1916) compares "the lowest rough and the smooths which come from the same parents."
- 26To stroke something, especially the fur of an animal, with the flat of the hand.
He liked to smooth the old dog's ears while reading.
She smoothed the horse's neck to calm it before the ride.
Note
A West Country use, in which smooth does the work of stroke. In that dialect, "Can I smooth your cat?" is a friendly request to pet the animal, not an offer to groom it. Elsewhere, listeners may hear it as flattening fur rather than petting. Away from the region, stroke or pet is the clearer word, while locally the verb is warm and ordinary.
- 27A member of a 1970s British youth movement that favored neat, fashionable dress in reaction against hippie style.
Every smooth on the street wore pressed slacks and a clean shirt.
The smooths looked down on the scruffy crowd at the festival.
Note
A name from British street style rather than texture. Peter Childs and Mike Storry's Encyclopedia of Contemporary British Culture (1999) places the smooths beside the suedeheads, among the styles that skinhead culture mutated into in the early 1970s. The name describes the look: neat and groomed, in pointed contrast to hippie dress.
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Origin
From Middle English smothe (also smethe), from Old English smēþe and smōþ, both from Proto-West Germanic *smanþī, of unknown origin. It is related to Scots smuith, Saterland Frisian smoud, Low German smood, and Dutch smeuïg, all meaning 'smooth'.