adjective

1. 1. having an even or level surface; having no roughness or projections that can be seen or felt
   2. having its projections leveled by wear a smooth tire
2. having an even consistency; without lumps a smooth paste
3. even, calm, or gentle in flow or movement a smooth voyage
4. free from interruptions, obstacles, difficulties, etc. smooth progress
5. not easily agitated or ruffled; calm; serene a smooth temper
6. free from hair, beard, etc.
7. pleasing to the taste; not sharp or harsh; bland
8. having an easy, gentle, flowing rhythm or sound
9. ☆ suave, polished, or ingratiating, esp. in a flattering, insincere way
10. ☆ Informal polished; competent a smooth dancer
11. Slang very pleasant, attractive, or enjoyable
12. Mech. having relatively little friction
13. Phonet. articulated without aspiration

Etymology: ME smothe < OE smoth, for earlier smethe < Gmc *smanthi < IE *som-, together < base *sem-, together, same

transitive verb

1. to make level or even
2. to remove the lumps from
3. to remove wrinkles from by pressing
4. to free from interruptions, difficulties, etc.; make easy
5. to make calm or serene; soothe
6. to make less crude; polish or refine

intransitive verb

adverb

noun

1. something smooth; smooth part
2. an act of smoothing