As Victoria Fromkin points out, "When the meaning of a word becomes broader, it means everything it used to mean and more" (An Introduction to Language, 2013).
- Historical Linguistics
- How Word Meanings Change
- Introduction to Etymology
- Key Dates in the History of the English Language
- Language Change
- Semantic Change
Examples and Observations:
- "Broadening of meaning . . . occurs when a word with a specific or limited meaning is widened. The broadening process is technically called generalization. An example of generalization is the word business, which originally meant 'the state of being busy, careworn, or anxious,' and was broadened to encompass all kinds of work or occupations."
(Sol Steinmetz, Semantic Antics: How and Why Words Change Meaning. Random House, 2008)
"Sometimes the use of existing words can become broader. For example, the slang word cool was originally part of the professional jargon of jazz musicians and referred to a specific artistic style of jazz (a use that was itself an extension). With the passage of time, the word has come to be applied to almost anything conceivable, not just music; and it no longer refers just to a certain genre or style, but is a general term indicating approval of the thing in question."
(Adrian Akmajian, Richard Demers, Ann Farmer, and Robert Harnish, Linguistics: An Introduction to Language and Communication. The MIT Press, 2001)
- Dog and Bird
"Quite a number of words have undergone semantic broadening in the history of English. The modern English word dog, for example, derives from the earlier form dogge, which was originally a particularly powerful breed of dog that originated in England. The word bird derives from the earlier word bridde, which originally referred only to young birds while still in the nest, but it has now been semantically broadened to refer to any birds at all."
(Terry Crowley and Claire Bowern, An Introduction to Historical Linguistics, 4th ed. Oxford University Press, 2010)
- Religious Terms
"Extension or Generalization. A lexeme widens its meaning. Numerous examples of this process have occurred in the religious field, where office, doctrine, novice, and many other terms have taken on a more general, secular meaning."
(David Crystal, The Cambridge Encyclopedia of the English Language. Cambridge University Press, 2003)
"An example of broadening of meaning is the change from holy day as a religious feast to the very general break from work called a holiday."
(George Yule, The Study of Language, 3rd ed. Cambridge University Press, 2006)
- Bleaching and Grammaticalization
"Thing used to refer to an assembly or council, but in time came to refer to anything. In modern English slang, the same development has been affecting the word shit, whose basic meaning 'feces' has broadened to become synonymous with 'thing' or 'stuff' in some contexts (Don't touch my shit; I've got a lot of shit to take care of this weekend). If a word's meaning becomes so vague that one is hard-pressed to ascribe any specific meaning to it anymore, it is said to have undergone bleaching. Thing and shit above are both good examples. When a word's meaning is broadened so that it loses its status as a full-content lexeme and becomes either a function word or an affix, it is said to undergo grammaticalization."
(Benjamin W. Forston IV, "An Approach to Semantic Change." The Handbook of Historical Linguistics, ed. by Brian D. Joseph and Richard D. Janda. Wiley-Blackwell, 2003)