plane

1 of 6

noun (1)

ˈplān 

1

a

[by shortening] : airplane

b

: one of the main supporting surfaces of an airplane

2

a

: a surface in which if any two points are chosen a straight line joining them lies wholly in that surface

b

: a flat or level surface

3

: a level of existence, consciousness, or development

on the intellectual plane

plane

2 of 6

verb (1)

planed; planing

transitive verb

1

a

: to make smooth or even : level

b

: to make smooth or even by use of a plane

2

: to remove by or as if by planing

—often used with away or off

intransitive verb

1

: to work with a plane

2

: to do the work of a plane

planer noun

plane

3 of 6

noun (2)

: a tool for smoothing or shaping a wood surface

Illustration of plane

• ³plane

plane

4 of 6

noun (3)

: any of a genus (Platanus of the family Platanaceae, the plane-tree family) of chiefly deciduous trees with large palmately lobed leaves, flowers in globose heads, and usually scaling bark

called also buttonwood, plane tree, sycamore

plane

5 of 6

verb (2)

planed; planing

intransitive verb

1

a

: to fly while keeping the wings motionless

b

: to skim across the surface of the water

2

: to travel by airplane

plane

6 of 6

adjective

1

: having no elevations or depressions : flat

2

a

: of, relating to, or dealing with geometric planes

b

: lying in a plane

a plane curve

Synonyms of plane

Noun (1)

• airplane
• aeroplane

Verb (1)

• smooth
• shave

Verb (2)

• fly
• wing
• hover

Adjective

• level
• smooth
• flat
• horizontal
• exact

Choose the Right Synonym for plane

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

Examples of plane in a Sentence

Noun (1)

a plane flew overhead

Verb (1)

planed the wood for the picnic table perfectly smooth so that no one would get splinters

Verb (2)

an eagle planed effortlessly overhead, gliding on an air current

Adjective

you can do these tracings on any plane surface

Recent Examples on the Web

Noun

Chief Critic Democratic Party consultant and former President Barack Obama’s ex-campaign adviser David Axelrod criticized the White House’s decision to use the old plane as a decoy with journalists on board. — Siladitya Ray, Forbes.com, 11 Aug. 2026

As the plane circled and prepared to return to the airport and emergency crews assembled, operations workers found the remains of the birds on the runway. — Amanda Jackson, CNN Money, 11 Aug. 2026

The Washington Post was first to report on the secret plane-switching. — Jennifer Jacobs, CBS News, 11 Aug. 2026

That line slices the plane into two halves, one of which will contain two corners of the outer triangle (the bottom half in the figure below). — Jack Murtagh, Scientific American, 10 Aug. 2026

Word History

Etymology

Noun (1)

Latin planum, from neuter of planus level

Verb (1)

Middle English, from Anglo-French planer, from Late Latin planare, from Latin planus level — more at floor

Noun (2)

Middle English, from Anglo-French, from Late Latin plana, from planare

Noun (3)

Middle English, from Anglo-French, from Latin platanus, from Greek platanos; probably akin to Greek platys broad — more at place

Verb (2)

Middle English, from Middle French planer, from plain level, plain

Adjective

Latin planus

First Known Use

Noun (1)

1604, in the meaning defined at sense 2a

Verb (1)

14th century, in the meaning defined at transitive sense 1a

Noun (2)

14th century, in the meaning defined above

Noun (3)

14th century, in the meaning defined above

Verb (2)

15th century, in the meaning defined at sense 1a

Adjective

14th century, in the meaning defined at sense 1

Phrases Containing plane

• aerospace plane
• block plane
• Cartesian plane
• complex plane
• equatorial plane
• focal plane
• half plane
• inclined plane
• jack plane
• London plane
• plane angle
• plane geometry
• plane of polarization
• plane-polarized
• plane table
• pontoon plane
• pursuit plane
• rocket plane
• tangent plane

Rhymes for plane

• ane
• bane
• blain
• brain
• cane
• chaine
• cheyne
• deign
• drain
• fain
• fane
• feign

Kids Definition

plane

1 of 5 verb

ˈplān 

planed; planing

1

: to make smooth or level especially with a plane

2

: to remove by planing

—often used with away or off

planer noun

plane

2 of 5 noun

: a tool for smoothing or shaping wood

plane

3 of 5 noun

1

a

: a surface in which a straight line joining any two points on the surface also lies completely on the surface

b

: a flat or level surface

2

: a level of existence or development

on the intellectual plane

3

a

: one of the main supporting surfaces of an airplane

b

: airplane

plane

4 of 5 adjective

1

: having no elevations or depressions : flat

2

a

: of, relating to, or dealing with planes

plane geometry

b

: lying within a plane

a plane curve

plane

5 of 5 verb

planed; planing

1

: to fly while keeping the wings still

2

: to travel by airplane

Etymology

Verb

Middle English planen "to make smooth or level," from early French planer (same meaning), derived from Latin planus "level" — related to plain entry 1

Adjective

from Latin planus "level"

Verb

from French planer "to fly while keeping the wings motionless," from plain "level, plain"; so called from the fact that the wings of a soaring bird form a level surface

Medical Definition

plane

noun

ˈplān 

1

a

: a surface that contains at least three points not all in a straight line and is such that a line drawn through any two points in it lies wholly in the surface

b

: an imaginary plane used to identify parts of the body or a part of the skull see frankfort horizontal plane, midsagittal plane

2

: a stage in surgical anesthesia

a light plane of anesthesia is maintained with cyclopropane

—The Journal of the American Medical Association