part of speech

noun Grammar.
  1. any of the classes into which words in some languages, as Latin and English, have traditionally been divided on the basis of their meaning, form, or syntactic function, as, in English, noun, pronoun, verb, adverb, adjective, preposition, conjunction, and interjection.

Origin of part of speech

First recorded in 1500–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for part of speech

part of speech

noun
  1. a class of words sharing important syntactic or semantic features; a group of words in a language that may occur in similar positions or fulfil similar functions in a sentence. The chief parts of speech in English are noun, pronoun, adjective, determiner, adverb, verb, preposition, conjunction, and interjectionAbbreviation: POS
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for part of speech
n.

c.1500, translating Latin pars orationis (see parse). Noun, adjective, pronoun, verb, adverb, preposition, conjunction, and interjection. Sometimes article and participle are counted among them.

Online Etymology Dictionary, © 2010 Douglas Harper