Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary


adjective \ˈsmüth\

Simple Definition of smooth

  • : having a flat, even surface : not rough : not having any bumps, ridges, or uneven parts

  • of a liquid mixture : not having any lumps : mixed together so there are no lumps

  • : happening or done without any problems

Source: Merriam-Webster's Learner's Dictionary

Full Definition of smooth

  1. 1a (1) :  having a continuous even surface (2) of a curve :  being the representation of a function with a continuous first derivative (3) :  having or being a short even coat of hair <a smooth collie> — compare rough, wirehairedb :  being without hairc :  glabrous <a smooth leaf>d :  causing no resistance to sliding

  2. 2 :  free from difficulties or impediments <the smooth course of his life>

  3. 3 :  even and uninterrupted in flow or flight

  4. 4 :  excessively and often artfully suave :  ingratiating <a smooth operator>

  5. 5a :  serene, equable <a smooth disposition>b :  amiable, courteous

  6. 6a :  not sharp or harsh <a smooth sherry>b :  free from lumps

smooth adverb
smoothly adverb
smoothness noun

Examples of smooth in a sentence

  1. They groomed the ski trail so it was smooth.

  2. The river rocks had been worn smooth by the water.

  3. Whisk the flour into the gravy until it is smooth.

  4. The milkshake was smooth and creamy.

  5. With the aid of observers, the election process was a smooth one.

  6. Our trip was smooth and uneventful.

  7. the smooth movements of a swimmer

  8. She has a nice, smooth golf swing.

  9. His new car has a smooth ride.

  10. Our flight was very smooth.

Origin of smooth

Middle English smothe, from Old English smōth; akin to Old Saxon smōthi smooth

First Known Use: before 12th century

Synonym Discussion of smooth

level, flat, plane, even, smooth mean having a surface without bends, curves, or irregularities. level applies to a horizontal surface that lies on a line parallel with the horizon <the vast prairies are nearly level>. flat applies to a surface devoid of noticeable curvatures, prominences, or depressions <the work surface must be flat>. plane applies to any real or imaginary flat surface in which a straight line between any two points on it lies wholly within that surface <the plane sides of a crystal>. even applies to a surface that is noticeably flat or level or to a line that is observably straight <trim the hedge so it is even>. smooth applies especially to a polished surface free of irregularities <a smooth skating rink>.

easy, facile, simple, light, effortless, smooth mean not demanding effort or involving difficulty. easy is applicable either to persons or things imposing tasks or to activity required by such tasks <an easy college course>. facile often adds to easy the connotation of undue haste or shallowness <facile answers to complex questions>. simple stresses ease in understanding or dealing with because complication is absent <a simple problem in arithmetic>. light stresses freedom from what is burdensome <a light teaching load>. effortless stresses the appearance of ease and usually implies the prior attainment of artistry or expertness <moving with effortless grace>. smooth stresses the absence or removal of all difficulties, hardships, or obstacles <a smooth ride>.

suave, urbane, diplomatic, bland, smooth, politic mean pleasantly tactful and well-mannered. suave suggests a specific ability to deal with others easily and without friction <a suave public relations coordinator>. urbane implies high cultivation and poise coming from wide social experience <an urbane traveler>. diplomatic stresses an ability to deal with ticklish situations tactfully <a diplomatic negotiator>. bland emphasizes mildness of manner and absence of irritating qualities <a bland master of ceremonies>. smooth suggests often a deliberately assumed suavity <a smooth salesman>. politic implies shrewd as well as tactful and suave handling of people <a cunningly politic manager>.

Rhymes with smooth




Simple Definition of smooth

  • : to make (something) smooth

  • : to remove problems or difficulties from a situation

  • : to spread (something) over a surface (such as your skin) : to apply (something) by rubbing it on a surface

Source: Merriam-Webster's Learner's Dictionary

Full Definition of smooth

smoothedsmoothingsmooths also smoothes

  1. transitive verb
  2. 1 :  to make smooth

  3. 2a :  to free from what is harsh or disagreeable :  polish <smoothed out his style>b :  soothe

  4. 3 :  to minimize (as a fault) especially in order to allay anger or ill will <his main job is to smooth over the friction that so often arises — Brian Crozier>

  5. 4 :  to free from obstruction or difficulty <conciliation smoothed the way to an agreement>

  6. 5a :  to press flat <smoothed down the folds of her dress>b :  to remove expression from (one's face) :  compose

  7. 6 :  to cause to lie evenly and in order :  preen <a bird smoothing its feathers>

  8. 7 :  to free (as a graph or data) from irregularities

  9. intransitive verb
  10. :  to become smooth

smoother noun

Examples of smooth in a sentence

  1. He smoothed his tie and headed out the door.

  2. The coin's date had been smoothed away over time.

  3. Smooth the cream on after your shower.

  4. Smooth the wax over the wood before polishing.

  5. She smoothed on some moisturizer before she put on her makeup.

  6. He smoothed ointment over the cut.

15th Century

First Known Use of smooth

15th century




Definition of smooth

  1. 1 :  a smooth part

  2. 2 :  the act of smoothing

  3. 3 :  a smoothing implement

15th Century

First Known Use of smooth

15th century

SMOOTH Defined for Kids



adjective \ˈsmüth\

Definition of smooth for Students


  1. 1 :  not rough or uneven in surface <a smooth board>

  2. 2 :  not hairy <a smooth face>

  3. 3 :  free from difficulties or things in the way <a smooth path> <a smooth journey>

  4. 4 :  moving or progressing without breaks, sudden changes, or shifts <a smooth stream> <smooth speech>

  5. 5 :  appearing to be friendly and flattering without really meaning it <a smooth talker>

smoothly adverb
smoothness noun




Definition of smooth for Students


  1. 1 :  to remove bumps, lumps, or wrinkles :  make smooth

  2. 2 :  to free from trouble or difficulty <Pioneers smoothed the way for us.>

Medical Dictionary


adjective \ˈsmüth\

Medical Definition of smooth

  1. :  forming or being a colony with a flat shiny surface usually made up of organisms that form no chains or filaments, show characteristic internal changes, and tend toward marked increase in capsule formation and virulence—used of dissociated strains of bacteria; compare rough

Seen and Heard

What made you want to look up smooth? Please tell us where you read or heard it (including the quote, if possible).


to dishevel or rumple

Get Word of the Day daily email!


Take a 3-minute break and test your skills!


Which of these is a synonym of nonplus?

disapprove reduce soothe perplex
Name That Thing

Test your visual vocabulary with our 10-question challenge!


Test Your Knowledge - and learn some interesting things along the way.