Earlier this week, Pres. Barack Obama sent Americans running to the dictionary when he called Democrats opposing his compromise on tax cuts "sanctimonious."
At a Dec. 7 press conference, the president accused Republicans of holding middle-class tax cuts hostage and scolded those Democrats taking an uncompromisingly "purist" position against the tax-cut extension: it allows us to "feel good about ourselves and sanctimonious about how pure our intentions are," but in the end it prevents us from getting anything done.
After the president spoke, Merriam-Webster’s online dictionary reported a spike in look-ups for sanctimonious.
Americans are used to consulting their dictionaries to confirm that when politicians say words like refudiate and misunderestimate they aren’t really words, or at least they're not words found in dictionaries. But whatever you think of the tax cuts, it’s refreshing—and not just refreshing for lexicographers—when a president talks policy and gives a vocabulary lesson at the same time.
Sanctimonious is actually two syllables shorter than George Bush’s classic misunderestimated, and it’s been an English word for a whole lot longer, but Pres. Obama’s unscripted “sanctimonious” triggered another “cling to their guns and their religion” moment for him.
At a San Francisco campaign rally in 2008, Mr. Obama had said of small-town Pennsylvanians who’d been waiting for years for their local economy to recover,
So it’s not surprising then that they get bitter, they cling to guns or religion or antipathy to people who aren’t like them or anti-immigrant sentiment or anti-trade sentiment as a way to explain their frustrations.
I’m not sure how many people listening to that speech had to go and look up antipathy—probably they all stopped listening after the guns and religion part. But the comment, which was essentially accurate but which Obama later said he could have phrased better, was used as evidence by the right wing that the senator lacked the common touch. In contrast, calling opposition Democrats “sanctimonious” is evidence for left-wingers that the president lacks the common touch.
If you were hoping to save a trip to the dictionary, I can tell you that sanctimonious, like purist and hostage-taker, is a negative term. The Oxford English Dictionary finds the earliest occurrence of the word in 1604, with the meaning ‘holy in character,’ a sense that is now obsolete. But by 1611 or so Shakespeare had used sanctimonious to signify ‘pretended piety,’ the sense that the word retains today.
Mark Twain used sanctimonious in a letter to the Daily Alta California in 1867, describing a fellow-passenger on a voyage to the Holy Land who acted morally superior to everyone else as "a solemn, unsmiling, sanctimonious old iceberg that looked like he was waiting for a vacancy in the trinity."

Daily Alta California, Aug. 18, 1867, p. 1
I don’t know how many Californians rushed to the dictionary after reading that. After all, Mark Twain was a humorist acknowledged to have the common touch. Abraham Lincoln was described as “the great commoner” despite the fact that, like Twain, he often used big words interspersed with more folksy diction: the audience listening to Lincoln’s speech at Gettysburg needed both a dictionary and a calculator to figure out how long “four score and seven years ago” actually was (today they can find the answer on Google in 0.11 seconds).

First paragraph of the Gettysburg Address, in Lincoln’s handwriting (John Nicolay copy, from the Library of Congress).
Barack Obama uses long words as well as short ones, often beginning his response to a reporter’s question with “Look . . . . ,” a word which no one needs to look up. But during the 2008 presidential campaign he was criticized for sounding too professorial--not surprising since he had been a college professor--and Obama’s language was a key element in the pre-election debate over whether he was black enough, since even in his more relaxed moments he didn’t sound much like Al Sharpton or 50 Cent.

In this episode of Talking Points Media, FoxNews takes the president to task for using big words like allegedly
Pretty much whatever happens shakes someone’s confidence that they know what a word means, and so they turn to dictionaries. According to Merriam-Webster, the top 10 words looked up in its online dictionary are pretentious, ubiquitous, love, cynical, apathetic, conundrum, albeit, ambiguous, integrity, and the affect/effect pair. The day after Sarah Palin tweeted refudiate, there was a surge in look-ups for both refute, which is in the dictionary, and refudiate, which is not. As the BP oil spill story captured headlines, many Americans felt the need to look up the meaning of seepage. The World Cup, with its annoying vuvuzela sound track, sparked inquiries about cacophony. When the movie Inception opened, look-ups for the title word soared, though it’s not clear that knowing what “inception” means could actually help viewers understand what Inception means. And when it became known during her confirmation hearings that Supreme Court nominee Elena Kagan had used the word “vapid” in a book review way back in 1995, inquiring minds wanted to know what she meant by vapid and whether her use of the word constituted judicial activism.
So it’s not just the president who sends Americans to the dictionary. But more important, Obama, the first president since Jack Kennedy who doesn’t feel the need to hide his intelligence from the cameras, who seems comfortable being himself rather pretending to voters, “I am you” as many politicians do, should be celebrated, not condemned, if he sends his audience to the dictionary now and then. That’s a lot better than sending them scurrying (‘moving hastily or rapidly’) to fallout shelters (‘something which affords a refuge from . . . nuclear fall-out') or high-tailing it (‘moving at full speed or rapidly’) for the Canadian border.

And speaking of vocabulary look-ups triggered by the news, anyone tempted to search for tea party in the OED won’t find a reference to the midterm elections but might be interested to learn that, among other things, tea party is slang for “a gathering at which marijuana is smoked,” and when used attributively it means, “held to be typical of a tea-party; bland, insipid, trite, trivial.”

Christine O’Donnell posted this video on YouTube in October. She begins by saying she is not a witch, followed by the claim, “I am you.”
Follow up re antipathy: Merriam-Webster informs me that there was a spike in look-ups of antipathy right after then-Senator Obama made his comment about "guns and religion." It was the top news-related word searched for the week beginning April 11, 2008.