word class

Definition:

A set of words that display the same formal properties, especially their inflections and distribution. Similar to the more traditional term "part of speech."

Observations:

• "When linguists began to look closely at English grammatical structure in the 1940s and 1950s, they encountered so many problems of identification and definition that the term part of speech soon fell out of favour, word class being introduced instead. Word classes are equivalent to parts of speech, but defined according to strict linguistic criteria."
  (David Crystal, The Cambridge Encyclopedia of the English Language, 2nd edition, Cambridge University Press, 2003)



• "[The] distinction between lexical and grammatical meaning determines the first division in our classification: form-class words and structure-class words. In general, the form classes provide the primary lexical content; the structure classes explain the grammatical or structural relationship. We can think of the form-class words as the bricks of the language and the structure words as the mortar that holds them together.
  
  

  FORM CLASSES (also known as LEXICAL CLASSES or OPEN CLASSES)
  
  Noun
  Verb
  Adjective
  Adverb
  

  STRUCTURE CLASSES (also known as FUNCTION CLASSES or CLOSED CLASSES)
  
  Determiner
  Pronoun
  Auxiliary
  Conjunction (or Conjunct)
  Qualifier
  Interrogative
  Preposition
  Expletive
  Particle

  "Probably the most striking difference between the form classes and the structure classes is characterized by their numbers. Of the half million or more words in our language, the structure words--with some notable exceptions--can be counted in the hundreds. The form classes, however, are large, open classes; new nouns and verbs and adjectives and adverbs regularly enter the language as new technology and new ideas require them."
  (Martha Kolln and Robert Funk, Understanding English Grammar, Allyn and Bacon, 1998)

Also Known As: grammatical category, part of speech