Open Class Words in English Grammar

Glossary of Grammatical and Rhetorical Terms

open-class words
The category of open-class words overlaps with the category of content words. M. Lynne Murphy notes that the open classes "are marked by the range and richness of the meanings they encode" ( Lexical Meaning, 2010). (Gregor Schuster/Getty Images)

In English grammar, open class refers to the category of content words—that is, parts of speech (or word classes) that readily accept new members, as contrasted with closed class, which do not. The open classes in English are nouns, lexical verbs, adjectives, and adverbs. Research supports the view that open-class words and closed-class words play different roles in sentence processing.  

The Importance of Open-Class Words

Open-class words comprise a large portion of any language. Unlike closed-class words, which are finite, the possibility of creating and adding new words to an open word-class is practically infinite.

"All the words in a language can be broadly divided into two categories, open and closed," writes Thomas Murray in "The Structure of English," explaining that the closed category does not readily accept new words. "Its members are fixed and do not usually change." Nouns, verbs, adverbs, and descriptive adjectives are, as he puts it, "exactly those parts of speech that remain open to new additions."

Murray goes on to say that words in the open category are usually divided into simple and complex words. "Simple words contain just one morpheme (for example, house, walk, slow, or green), whereas complex words contain more than one morpheme (such as houses, walking, slowly, or greenest)."

Open-Class Words in Telegraphic Speech

One archaic form of language in which the distinction between open-class words and closed-class words is especially evident is what's known as telegraphic speech. The term telegraphic is based on the wording style that was commonly used in telegrams. (Western Union sent the last telegram in the U.S. back in 2006. The final telegram in the world was tapped out in India in 2013.)

The format required senders to squeeze as much information into as few words as possible. It's hard to imagine now, but back in the day, every letter and space in a telegram cost money. The less said, the more powerful the message, and also the more economical. Telegrams also had a sense of immediacy. Even though they had to be hand-delivered, they were the closest thing to instant communication available prior to the invention of the telephone and were generally sent to impart important information that required a timely response.

For example, if a college student traveling abroad wanted to make sure his parents were at the airport to pick him up upon his return, he might send them a telegram along the lines of: "HAVING WONDERFUL TIME; HOTEL GREAT; RETURNING THURSDAY; FLIGHT 229 KENNEDY; MEET ME." As you can see, in the telegraphic forms of language, the crucial open-class words take precedence, while the closed-class words are edited out whenever possible.

Telegraphic language has evolved to include many forms of information exchange inherent to the Internet and texting. Tweets, metadata, SEO (search engine optimization), and texts all rely heavily on abbreviated content similar to the format once used in telegrams (although, leaving your caps-lock on is no longer a preferred or even desired choice stylistically speaking—unless you're YELLING!).

How Open-Class Words Become Part of a Language

One of the ways by which new open-class words become part of a language is a process known as grammaticalization, which happens, usually over the course of time, when a word or set of words undergoes a semantic change that results in a revised lexical meaning or grammatical function. Keeping up with this word evolution the reason dictionaries are routinely updated.

In "Grammatical Analysis and Grammatical Change" Edmund Weiner cites the verb "ought" as an example: "[Ought] has evolved from being the past tense of to owe to the condition of a pure auxiliary." Weiner goes on to explain that "open-class words can develop senses that constitute fully grammaticalized lexical items while retaining their original character in their other senses." Another method open-class words are developed notes Weiner, is "from compounds that start out as straightforward syntactic constructions, for example, as and also from all so."

Portmanteau Open-Class Words

One form of open-class words that are finding their way into more and more dictionaries are portmanteau words, which are what happens when two words are merged together to create a meaning that carries aspects of the two original words. The word "portmanteau" is itself such a combined word, taken from the French verb porter, meaning "to carry, and manteau, meaning "cloak" or "mantle." When applied to luggage, the combined phrase means something in which one carries an article or two of clothing. When applied to language, it means one word packed with two slightly altered meanings.

While modern technology is rife with open-class portmanteau words— email (electronic + mail), emoticon (emotions + icons), podcast (iPod + broadcast) freeware (free + software), malware (malicious + software), netizen (Internet + citizen), and netiquette (Internet + etiquette), to name just a few—there are plenty of portmanteaus you might not even know are portmanteaus. Smog? That's smoke plus fog. Brunch? Breakfast plus lunch.

Of course, the most amusing class of portmanteau words are those that developed as a result of sharp minds and wicked senses of humor, and include such gems as chillax (chill + relax), bromance (brother + romance), mockumentary (mock + documentary), and finally, ginormous (gigantic + enormous), which made the cut with the keepers of the Oxford English Dictionary in 1989, albeit as “slang” (although Merriam-Webster's counts the relatively new open-class word as “authentic”).

SPAM® (as in the trademarked canned-meat product from the Hormel Company) is a portmanteau word that originally combined the words "spice" and "ham." Now, however, thanks to open-word evolution, the word is generally defined as "mass unsolicited junk email." If you're wondering how SPAM became spam, etymologists give credit to the crew from Monty Python and their "SPAM" sketch, in which every item on the menu of a particular eatery contained ubiquitous and sometimes copious amounts of the prefab canned meat product.

Other Relevant References


  • Murray, Thomas E. "The Structure of English." Allyn and Bacon. 1995
  • Akmajian, Adrian; et al., "Linguistics: An Introduction to Language and Communication." MIT. 2001
  • Weiner, Edmund. "Grammatical Analysis and Grammatical Change." "The Oxford Handbook of Lexicography." Durkin, Philip: Editor. Oxford University Press. 2015
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Your Citation
Nordquist, Richard. "Open Class Words in English Grammar." ThoughtCo, Aug. 25, 2020, Nordquist, Richard. (2020, August 25). Open Class Words in English Grammar. Retrieved from Nordquist, Richard. "Open Class Words in English Grammar." ThoughtCo. (accessed May 29, 2023).