Difference Between Plane and Plain (With Table)

Two homonyms that signify flatness are plane and plain. There is a common misconception regarding plain and plane. They denote the same thing in one sense but are utterly different. The most common meanings of plain and plane are simple, but the most perplexing usage of ‘plain’ and ‘plane’ are two distinct nouns.

Plane vs Plain

The main difference between plane and plain is that plane can be a noun or verb. On the other hand, plain can be a noun, adjective, or adverb. Though both refer to uniformity or flatness, the plane is more geometry related, and the plain is specifically geography oriented.

A plane, as a noun, can mean several things in our daily- life, such as it can be an aeroplane, a level surface of anything or a tool for levelling wood. As a verb, it is an act of smoothing or levelling something. It is a state of being or awareness within a spiritual or religious context.

Plain is an adjective that describes something straightforward, uncomplicated, or obvious. Plain usually refers to a flat, treeless area of the terrain. They are a prime landform on land and are necessary for large-scale agriculture. The Atlantic Coastal Plain of the United States East Coast is one of the most well-known examples.

Comparison Table Between Plane and Plain

Parameters of Comparison




It is a flat surface above the ground.

It is a flat surface on the ground.


First recorded in 1375–1425 from middle English word plaine, pleine.

First known use in the 14th century from the Middle English word ‘planum’.


It is supposed to exist in a vacuum.

A continuous process of deposition and sedimentation creates it.


Mathematicians use it primarily to solve problems in geometry.

In geography, it has a lot of significance for agriculture and farming.


The only thing left to do was pack and take a plane home.
He proved the law of equilibrium on an inclined plane.

Her room was plain and basic.
The interior, plain in itself, contains eye-catching sculptures.

What is a Plane?

A plane is a two-dimensional flat surface of an infinite height and width in geometry. It is a fundamental element in geometry. The word plane first appears in a mathematical context in the early 1600s. It derives from the Latin word plānum, which means ‘flat surface’, and the Latin adjective plānus, which means flat.

The English word plane can have different meanings and usage in different kinds of sentences such as:

a vehicle with wings and designed for air travel;

For example, He is scared of travelling by plane.

A flat or level surface that spans in all directions in mathematics:

For example, Meena saw a building with angled planes.

A specific standard or level:

For example, His artistic work is of a different plane.

a tool for flattening and smoothing wooden surfaces and edges

For example, The carpenter forgot to bring his plane and equipment to work.

Some of the synonyms of a plane are aeroplane, craft, flat, even, horizontal, smooth, flush, grade, uniform, face, regular, degree, condition, extension, facet, footing, grade, horizontal, obverse.

Some of the antonyms of a plane are coarse, uneven, rough, unsmoothed, lumpy, bumpy.

Phrases Containing plane are the Cartesian plane, complex plane, equatorial plane, inclined plane, polarization plane, plane-polarized, plane table.

What is Plain?

A plain is a level tract of land with dainty variation in elevation and is mostly devoid of trees in geography. A ‘plain’ can occur as lowlands in valleys or at the foot of mountains, coastal plains, plateaus, or uplands.
When a geological region has more than one plain, a pass connects them called a gap. Coastal plains rise gradually from sea level until they reach higher terrain, such as mountains or plateaus.

Plains are one of the most common landforms on land, occupying more than one-third of the planet’s total area. There are plains on every continent. Lava can form mountains and plains, ice, rain, or wind can deposit sediment, or mountains and hills can erode the soil. Grassland, steppe, savannah, or tundra are some biomes found on plains. Deserts and rainforests may be called plains in some cases.

Plains are significant for agriculture in many locations because sediments deposited on plains may be deep and fertile. Also, the flatness promotes technology-driven crop production, or they sustain grasslands that give suitable grazing for livestock.

Common synonyms of ‘plain’ are bare, unadorned, down(s), grassland, unvarnished, pampa, tundra, simple.
Some antonyms of ‘plain’ are fancy, adorned, embellished, ornamented, decorated.

Main Differences Between Plane and Plain

  • A plane is a noun, adjective, and verb, whereas plain is an adjective adverb and noun.
  • A plane is a flat surface that is high above the ground. A flat surface on the earth is plain.
  • From the Middle English term plaine, pleine, the term ‘plane’ appears first between 1375 and 1425. ‘Planum’ was the Middle English term for plain in the 14th century.
  • A plane should be able to exist in a vacuum. Deposition and sedimentation are the processes that create a plain.
  • It is most commonly used in geometry to solve difficulties. Plains have a lot of relevance in geography for agriculture and farming.


As their part of speech changes, these homonyms change their meaning in sentences.
The plane represents angles and two-dimensional shapes such as squares, triangles, and circles as points, lines, and line segments. In addition, it assists in the cognizance of three-dimensional objects that include more than just length and width. There are various more definitions for the word plane, some of which have different etymologies. It can also apply to any flat or level surface in general.

It is also possible to discern the multiple meanings of the term plain by examining its varied grammatical roles. Plain is an adjective that refers to something simple, flat, or unadorned. Sometimes, plain also describes a person who does not have a lot of attractive qualities.


  • https://books.google.com/books?hl=en&lr=&id=oOWAnvkrD70C&oi=fnd&pg=PA417&dq=Difference+Between+Plane+and+Plain&ots=UriSHaFLOm&sig=2pfBSLgiL9oHp8ywp0uv4OcxcXY
  • https://link.springer.com/article/10.1007/s00586-010-1610-8