Word.ws English Dictionary

parallel postulate

parallel postulate noun: an axiom in Euclidean geometry: given a straight line L and a point p not on L, there exists exactly one straight line parallel to L that passes through p; a variant of this axiom, such that the number of lines parallel to L that pass through p may be zero or more than one.

Noun

parallel postulate (plural parallel postulates)

  1. An axiom in Euclidean geometry: given a straight line L and a point p not on L, there exists exactly one straight line parallel to L that passes through p; a variant of this axiom, such that the number of lines parallel to L that pass through p may be zero or more than one.
    • Before we examine the particulars of the parallel postulates of Hyperbolic and Elliptical geometries, we must see their logic.1962, Mary Irene Solon, The Parallel Postulates of Non-Euclidean Geometry: The Pentagon: A Mathematics Magazine for Students, Volumes 22-25, page 28
    • The earliest known attempt to prove the parallel postulates from the other axioms was by Ptolemy in about 150 A.D.1969, John B. Fraleigh, Mainstreams of Mathematics, Addison-Wesley, page 95
    Synonyms:
    Euclid's fifth postulate, triangle postulate

Synonyms of parallel postulate

Forms of parallel postulate

pluralparallel postulates

Origin of parallel postulate

From the reference to parallel lines in the definition as formulated below, following Scottish mathematician John Playfair; this wording leads to a convenient basic categorization of Euclidean and non-Euclidean geometries. The original formulation in Euclid's Elements makes no mention of parallels.

Questions about parallel postulate

What does parallel postulate mean?
Parallel postulate means an axiom in Euclidean geometry: given a straight line L and a point p not on L, there exists exactly one straight line parallel to L that passes through p; a variant of this axiom, such that the number of lines parallel to L that pass through p may be zero or more than one.
What part of speech is parallel postulate?
Parallel postulate is a noun.
What is the plural of parallel postulate?
The plural of parallel postulate is parallel postulates.

Words near parallel postulate in the dictionary

  1. parallel played
  2. parallel playing
  3. parallel plays
  4. parallel port
  5. parallel ports
  6. parallel postulate
  7. parallel postulates
  8. parallel processing
  9. parallel ruler
  10. parallel rulers
  11. parallel slalom

Source and license

Adapted from Wiktionary: parallel postulate (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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