Word.ws English Dictionary

X-bar theory

X-bar theory noun: a theory that posits a common syntactic structure for different lexical categories. Each phrase (XP) is the projection of a head (X) and may optionally include a specifier (sister of X-bar, daughter of XP), adjuncts (sister and daughter of X-bar) and complements (sister of X, daughter of X-bar).

Noun

X-bar theory (uncountable)

  1. A theory that posits a common syntactic structure for different lexical categories. Each phrase (XP) is the projection of a head (X) and may optionally include a specifier (sister of X-bar, daughter of XP), adjuncts (sister and daughter of X-bar) and complements (sister of X, daughter of X-bar).

Forms of X-bar theory

alternative formX′ theory

Origin of X-bar theory

X signifies an arbitrary lexical category; certain structures are represented by this letter and an overbar.

Words formed from X-bar theory

Questions about X-bar theory

What does X-bar theory mean?
X-bar theory means a theory that posits a common syntactic structure for different lexical categories. Each phrase (XP) is the projection of a head (X) and may optionally include a specifier (sister of X-bar, daughter of XP), adjuncts (sister and daughter of X-bar) and complements (sister of X, daughter of X-bar).
What part of speech is X-bar theory?
X-bar theory is a noun.

Words near X-bar theory in the dictionary

  1. x-axis
  2. x-band
  3. x-bands
  4. X-bar
  5. X-bar theoretic
  6. X-bar theory
  7. X-bar-theoretic
  8. X-box
  9. X-by-wire
  10. X-C
  11. x-caboquinho

Source and license

Adapted from Wiktionary: X-bar theory (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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