English English language Etymology Expression Linguistics Phrase origin Usage Word origin

Is “based off” off base?

Q: As I read the papers of college freshmen, I am often stopped by usages that seem wrong to me. The latest example is the use of “based off” for “based on,” as in “based off the research of Albert Einstein.” Your thoughts?

A: You’re not the first to notice the use of “based off” (sometimes “based off of”) in place of “based on,” though college students aren’t the only perpetrators.

Linguists have been discussing the usage for at least 10 years, and it was the subject of an online article in the Chronicle of Higher Education in October 2013.

The author of the article, Anne Curzan, wrote: “I have mentioned the construction to a few colleagues, and it’s clear at least some of them are circling it in student writing.”

The use is also found outside routine classroom writing. Curzan, a linguist and a professor of English at the University of Michigan, passed along this example from the academic journal Exceptional Children (March 2012):

“For our study, the parameters used in the simulation were based off of values derived from a large empirical data set.”

And we’ve found other recent examples of “based off” in academic journals, both American and British.

By the way, “based off of” is just a puffed up version of “based off.” Our suspicion is that people who use “based off of” may have the phrase “on the basis of” in mind.

We’ve written on the blog about “off of,” an extremely common redundancy. So we’ll confine these remarks to “based off.”

While “based off” may have become more popular recently, it’s not unseen in older writing. It’s been used occasionally since the early 1930s, mostly in trade journals.

The earliest example we’ve been able to confirm appeared in a May 1931 issue of National Petroleum News:

“To consumers: … discounts are based off tank wagon price, and affect purchases of 1,000 gallons or more per month” (this notation appeared several times in column listings).

Here it is again in 1952: “Based off 1951 figures, the proposed constitutional amendment would cut Federal revenues by $16,000,000,000 a year” (from the Bulletin of the Metal Trades Department of the American Federation of Labor).

And this headline appeared on a cover story in the trade journal Automotive News in January 1997: “Bigger Honda SUV will be based off Accord, minivan.”

These 20th-century appearances cropped up so seldom that nobody seems to have minded.

The use of “based off” in the sense of “based on” isn’t discussed in Merriam-Webster’s Dictionary of English Usage. And while Garner’s Modern English Usage (4th ed., 2016) has a long discussion of “based on,” it makes no mention at all of “based off.”

Discussions of “based off” have come up periodically on the Linguist List, the online discussion group of the American Dialect Society, but only in the last 10 years.

Writing on the list in 2006, Seán Fitzpatrick commented: “My daughters were discussing a forthcoming movie, and the 21-year-old said you had to give the auteur credit for originality, since the movie was ‘not based off a book, not based off another movie, and not based off a TV show.’ ”

“ ‘Based off’ seemed to me to be a peculiar alteration of ‘based on,’ ” Fitzpatrick added. “The strange thing is that she denied having said ‘based off’ instead of ‘based on.’ ”

Another contributor, the linguist Arnold Zwicky, suggested that “based off” as a variation on “based on” or “based upon” may be relatively recent.

“In any case,” Zwicky wrote, “it’s now very widespread.” And it’s become even more widespread since 2006.

Writing on the list in 2014, the slang lexicographer Jonathan Lighter reported a sighting of “based off” with another meaning: “as a result of; by reason of; from.”

The quotation, from Yahoo! news: “Hawking earned his scientific reputation back in the 1970’s based off his theory of black holes as cosmic vacuums.”

We won’t bother reporting the comparative frequency of “based off” versus “based on” in Google’s Ngram viewer, which tracks words and phrases in millions of books.

Many of the supposed examples of “based off” turn out to be misreadings of “eased off” or another phrase. And many other examples don’t represent the sense we’re talking about (e.g., “based off the coast of Cadiz”).

Though “based off” in place of “based on” sounds foreign to our ears, the usage doesn’t surprise us.

We’ve often remarked that the use of prepositions in English is highly idiomatic and subject to changing usage.

(A newcomer to English recently wrote to us in confusion about the various prepositions used in reference to copying: “print out,” “print off,” and “print up.” We explained that they’re all acceptable idioms.)

As Curzan wrote in her article: “With ‘based on’ one could argue that because things are physically built on bases, it makes more sense to say ‘based on.’ ”

“I agree: That is perfectly logical,” she added. “But language isn’t always logical, and once ‘based on’ becomes as much or more metaphorical than literal, it doesn’t seem surprising to me that the preposition might shift—especially given that one can metaphorically ‘build off’ things.”

We would add that a reinterpretation of a work is often called a “takeoff,” which may have contributed to the use of  “based off.”

“Based” here is the past participle of the verb “base,” and the Oxford English Dictionary has no examples of its use with “off.”

The OED says the verb means “to place on (also upon) a foundation, fundamental principle, or underlying basis.” (Note the prepositions in italics.)

All of the dictionary’s citations for this sense the verb and adjective, between 1776 and 2009, show the accompanying preposition as either “on” or “upon.”

As far as we can tell, people seem to use “based off” in three general ways:

● as a verb, either active (“She based her novel off Pride and Prejudice”) or passive (“Her novel is based off Pride and Prejudice”);

● as an adjective (“Figures based off speculation aren’t reliable”);

● as an adverb (“The company pays based off the hours worked”).

Now, we aren’t advocating any of these or claiming they’re standard English usage. We’re merely reporting what’s out there, so hold those indignant emails and tweets.

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