smooth

Etymology

From Middle English smothe, smethe, from Old English smēþe, smōþ, both from Proto-West Germanic *smanþī, of unknown origin. Cognate with Scots smuith (“smooth”), Low German smood and smödig (“smooth, malleable, ductile”), Dutch smeuïg (“smooth”) (from earlier smeudig).

adj

1. Having a texture that lacks friction. Not rough.
   Teaching that’s done by talking seems to have one rough path and another part which is smoother. 2005, Lesley Brown, Sophist, translation of original by Plato, page 229e
2. Without difficulty, problems, or unexpected consequences or incidents.
   We hope for a smooth transition to the new system.
   England's path to Poland and Ukraine next summer looked to be a smooth one as goals from Ashley Young and Darren Bent gave them a comfortable lead after 31 minutes. 2011, Phil McNulty, “Euro 2012: Montenegro 2-2 England”, in BBC
3. Bland; glib.
   This feeling, grounded on the experience of centuries of oppression, was not to be allayed by smooth explanations on the part of the advocates of the Constitution. 1912, Gustavus Myers, History of the Supreme Court of the United States, page 133
4. Flowing or uttered without check, obstruction, or hesitation; not harsh; fluent.
   the only smooth poet of those times 1670, John Milton, The History of Britain
5. Suave; sophisticated.
   He was so smooth and handsome. He knew just what to say and when to say it. 2003, T. Lewis Humphrey, The Price of Love, page 279
6. (of an action) Natural; unconstrained.
   In order for a reading to be smooth and effortless, readers must be able to recognize and read words accurately, automatically, and quickly. 2006, Mary Kay Moskal, Camille Blachowicz, Reading for Fluency, page 3
7. (of a motion) Unbroken.
   Demonstrate first by the numbers and then as one smooth movement. 1927, United States National Guard Bureau, Manual of Basic Training and Standards of Proficiency for the National Guard, page 181
8. (chiefly of water) Placid, calm.
   As we worked to the southward, we picked up fair weather, and enjoyed smooth seas and pleasant skies. 1898, John Donaldson Ford, An American Cruiser in the East, page 47
9. (of an edge) Lacking projections or indentations; not serrated.
   A leaf having a smooth margin, without teeth or indentations of any kind, is called entire. 1994, Robert E. Swanson, A Field Guide to the Trees and Shrubs of the Southern Appalachians, page 8
   Out of the handles flipped the smooth blade and the serrated blade, which was dangerously sharp, the flathead screwdrivers, the Phillips screwdriver, the can opener, the awl. 1997, Christopher Dickey, Innocent Blood: A Novel, page 91
10. (of food or drink) Not grainy; having an even texture.
    A compact and stylish design, it produces 1 generous quart of excellent, smooth ice cream in 20 to 25 minutes. 1997, Lou Seibert Pappas, Sorbets and Ice Creams, page 19
11. (of a beverage) Having a pleasantly rounded flavor; neither rough nor astringent.
    The coffee was smooth, so smooth she took another sip. 2002, Candace Irvin, For His Eyes Only, page 9
12. (mathematics, of a function) Having derivatives of all finite orders at all points within the function’s domain.
    Any ANALYTIC FUNCTION is smooth. But a smooth function is not necessarily analytic. 2003, Eric W. Weisstein, CRC Concise Encyclopedia of Mathematics, page 419
13. (mathematics, of a number) That factors completely into small prime numbers.
14. (linguistics, classical studies, of a vowel) Lacking marked aspiration.
    Οὐ becomes οὐκ before a smooth vowel, and οὐχ before an aspirate. 1830, Benjamin Franklin Fisk, A Grammar of the Greek Language, page 5
15. (of muscles, medicine) Involuntary and non-striated.

adv

1. Smoothly.

noun

1. Something that is smooth, or that goes smoothly and easily.
   Things are often equalized by roughs and smooths being set against one another. 1860, Anne Manning, The Day of Small Things, page 81
2. A smoothing action.
   She brushes down her hair with a little bit of spit and a smooth of her hand and opens the bright green door, walking a few metres, squinting. 2006, Julienne Van Loon, Road Story, page 12
3. A domestic animal having a smooth coat.
   In the 4-toe stock there is a wide gap between the lowest rough and the smooths which come from the same parents. 1916, William Ernest Castle, Sewall Wright, Studies of Inheritance in Guinea-pigs and Rats, page 104
4. A member of an anti-hippie fashion movement in 1970s Britain.
   By the early 1970s, skinhead culture began to mutate into the variant ‘white ethnic’ styles of the suedeheads and smooths. 1999, Peter Childs, Mike Storry, Encyclopedia of Contemporary British Culture, page 188
5. (statistics) The analysis obtained through a smoothing procedure.
   A smooth of the potato data set has already been given in Figure 1.2. 1990, Wolfgang Härdle, Applied Nonparametric Regression, page 17

verb

1. (transitive) To make smooth or even.
   She smooths her skirt, looking as composed and ladylike as possible. 1961, William Gibson, The Miracle Worker, page 37
2. (transitive) To reduce to a particular shape or form by pressure; to press, to flatten.
   to smooth cloth with a smoothing iron
3. (transitive) To make straightforward or easy.
   Caracas can be a tough place but the tremendously good-natured caraqueños smoothed my passage every step of the way. 2007, Beth Kohn, Lonely Planet Venezuela, page 379
4. (transitive) To calm or palliate.
   to smooth a person's temper
5. (statistics, image processing, digital audio) To capture important patterns in the data, while leaving out noise.
   […] the 7-month moving averages provide better smoothing of the data in this case than do the 3-month moving averages. 1999, Murray R. Spiegel, Larry J. Stephens, Schaum’s Outline of Theory and Problems of Statistics, page 457
6. (West Country) To stroke; especially to stroke an animal's fur.
   Can I smooth your cat?