adj · 5 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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General-American:/ˈpleɪnɚ/
Received-Pronunciation:/ˈpleɪnə/
Southern-England:Recorded audio is listed in the source snapshot.
homophone: plainer
homophone: planer
rhymes with -eɪnə(ɹ)
CMU ARPABET:P L EY1 N ER0
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
adj
Meaning 1
Of or pertaining to a plane.
Definition source: English Wiktionary via Wiktextract
Examples
A planar projection of a three-dimensional object is its projection onto a plane.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
adj
Meaning 2
Flat, two-dimensional.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
3
adj
Meaning 3
Able to be embedded in the plane with no edges intersecting.
Definition source: English Wiktionary via Wiktextract
Topics: graph-theory, mathematics, sciences
Examples
A complete graph with more than four nodes is never planar.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
4
adj
Meaning 4
Having a flat profile, not etched into a mesa.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
5
adjective
Meaning 5
involving two dimensions
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: two-dimensional
Antonyms: cubic, linear
History
Etymology
From Late Latin plānārius (“relating to a plane”), derived from Latin plānus (“flat”, “level”), equivalent to plane + -ar, ultimately from Proto-Indo-European *pleh2- (“flat”).
Across languages
Translations
14 source translations are retained for this English entry.
Bulgarian:
равнинен
(ravninen)
— of or pertaining to a plane