You know how animators and filmmakers will sometimes slip something a little unexpected into a piece just to put their stamp on it? They're not the only ones who do so. You'll find silly little entries in lots of other places - if you know what to look for. And sometimes the reason for the fictitious entry serves a purpose other than to amuse the author (see #4, #5 and #8). Check out these 10.

1. Apopudobalia. What, you've never heard of this sport? Don't feel too bad "“ neither have most people, and that's because it doesn't exist. But the German-language Der neue Pauly, a German encyclopedia Brittanica, didn't let the fact that the sport never was stop them from including it in their 1986 edition. According to the encyclopedia, it was a Greco-Roman sport similar to modern-day soccer.

2. Zzxjoanw. This one flew under the radar for years; it was reprinted in editions of The Musical Guide from 1903-1956. The Guide contained all kinds of information on music, including a 252-page dictionary for meanings and pronunciations of non-English words often found in music. "Zymbel," which is German for cymbal, should have been the last entry. However, author Robert Hughes slipped in "Zzxjoanw," apparently pronounced "shaw," and declared it a type of Maori drum. The hoax was fully exposed in a 1996 book called Making the Alphabet Dance. One pretty big tipoff that the word was fake: there is no "Z" in the Maori alphabet.

3. Lillian Virginia Mountweazel. The New Columbia Encyclopedia included a pretty unbelievable entry on this Ohioan in its 1975 edition. Mountweazel was a fountain designer and photographer and was particularly skilled at capturing the essence of rural mailboxes in America. She died in a freak explosion while on assignment for Combustibles magazine. The kicker? She was from Bangs, Ohio. Ha. For someone who doesn't exist, Lillian is quite accomplished - an art exhibit was dedicated to her "work" last year.

4. Esquivalience. Even the most well-known dictionaries slip one by people sometimes, but with good reason. In 2005, The New Oxford American Dictionary made the news when the faux word "esquivalience" was discovered amongst its other very real words. It was intended as a copyright trap "“ a purposeful error made to make it easy to spot plagiarizers. Given this purpose, the definition editors made up for it is pretty clever: "the willful avoidance of one's official responsibilities."

5. Jungftak. Yep, Websters does it too. A 1943 version of Webster's New Twentieth Century lists a jungftak as:

"A Persian bird, the male of which had only one wing, on the right side, and the female only one wing, on the left side; instead of the missing wings, the male had a hook of bone, and the female an eyelet of bone, and it was by uniting hook and eye that they were enable[d] to fly, -each, when alone, had to remain on the ground."

A professor wrote to Webster's in the "˜80s to ask about the, um, interesting entry, and its then-associate editor responded that the entry definitely lacked validity. She suspected it was used for the same copyright-protection reasons "esquivalience" had been in The New Oxford American Dictionary.

6. Dord. "Dord" is the result of a rather humorous error, although that error wasn't explained until 15 years after the fictitious word was printed in Webster's Third New International Dictionary. The word ostensibly meant "density." What actually happened was that the dictionary's chemistry editor sent a note that said "D or d, cont./density," meaning that the letter "d" could be used as an abbreviation for density. Somewhere along the line, the note was mistranslated as dord instead of "D or d."

7. Stone Louse. The stone louse is a fictitious little mite that gnawed its way into the German medical dictionary Pschyrembel Klinisches WÃ¶rterbuch in 1983. It was based on a parody nature documentary by the German humorist Loriot. It seems that most people caught on to the joke, because the stone louse remains in the dictionary, with each edition seeming to expand on the mite's habitat, medical value and natural enemies. Apparently the louse was instrumental in bringing down the Berlin Wall, as the wall was placed in areas "commonly inhabited by the stone louse." Who knew?!

8. Agloe, New York. Agloe is one of the few instances of a fictional place turning real. The fake town was included on a 1930s map for the same reason publishers put fake words in the dictionary "“ to deter anyone who might try to copy the map and sell it for their own profit. The joke was on them, though "“ when someone built a little general store at precisely the spot the fake town was labeled on the map, they named it the Agloe General Store because they thought that's what town they were legitimately in. Today, it's best known as a quirky landmark and for being featured in the young adult novel Paper Towns by John Green.

9. Guglielmo Baldini. The Grove Dictionary of Music and Musicians is the largest reference work on Western music ever. It's so large, in fact, it even contains some musicians who aren't real. Although the fictional Baldini appeared within the Grove's pages, it wasn't their editors who made him up. The fake composer was invented nearly 100 years earlier by musicologist Hugo Riemann. An eagle-eyed reader spotted the error and Baldini was removed by the second printing of the book.

10. Dag Henrik Esrum-Hellerup. Also an entry in The Grove, Esrum-Hellerup was added to the 1980 edition, perhaps in homage to the great Baldini. Like his predecessor, though, the hoax was quickly exposed, removed, and replaced with an illustration in the book.

Have you ever spotted an entry in the dictionary that didn't quite sound right to you? I'm almost motivated to go cull through my dictionaries to see if I can spot the fake entries. Almost.