Many of the people who follow the Dudes and read this blog are professionals involved in the teaching of English at some level or another. And whether that’s working with language impaired 3-year-olds, adults learning English as a second language, teenagers with literacy challenges, or folks using augmentative and alternative communication technology, having a grasp of word functions and meanings is critical. So if you’re looking for information about a word, where do you turn to?  The answer is, “the dictionary!”
Ah, but which dictionary, you may ask? Well, based on my many years of working with words, here is a set of recommendations that can’t fail to be of use. Each one is good in its own rights but for slightly different reasons. Nerds will want all seven but others will probably be just fine with two. Feel free to disagree but if you do, send a comment to explain why.
So here we go, with our number 7 slot going to….
7. The Urban Dictionary
Shocked as some folks might be that a language professional would recommend this, it’s truly an essential tool for finding out the meaning of slang words as used by the vox populi. It’s a user-defined dictionary that uses a voting system to determine how “real” a definition for a word may be – or even how “real” a word is! As an example, the word vurp has 8 definitions but the one with the most votes is, “a burp laced with a little vomit, usually occurs when you’ve had one too many and it has become difficult to distinguish between the two.”
References to current trends, fads, celebrities, and pop culture abound. So a gloatgram is, “an instagram post that features the user boasting about their life, usually in the form of food or leisure/travel,” or e-void means, “avoiding someone electronically such as on Facebook, e-mail, IM, or text messages.”
The lifespan of many words in the Urban Dictionary is slightly less than that of a May fly at a fly-swatters convention, but once you get past the decadently profane nature of many of the definitions , it can give you a unique insight into not just the minds of the masses but the way in which new words can be coined and constructed. 
6. The Macmillan Dictionary
The definitions from the Macmillan are short and include parts of speech, and you can also hear British English and American English pronunciations. The distinctive feature of this dictionary is that it marks the 7,500 most frequently used words in speech and writing. The highest frequency words get a 3-star rating, the lowest a 1-star. So want is a 3-star word whereas aspire only gets a 1-star. So if you are working with English learners, you can encourage folks to look for 3-star words as these are going to be more useful.
5. Oxford Dictionaries
The folks at Oxford University Press have been in the book business since the 15th century, and opened an office in the US in 1896. As publishers of the world-renowned Oxford English Dictionary, these guys know what they’re doing. So it’s inevitable that we’re including at least one of their dictionary offerings in a Top 7 list. The online Oxford Dictionaries is free, offers simple definitions along with a brief etymology, and a drop-down menu to switch between US English and British/Word English – great for those of us who write and work on an international platform.
If you want a simple but comprehensive free dictionary for your smartphone, this is a great choice. In its latest incarnation on my Droid, the interface is clean, simple, and the definitions are short and typically fit on a single screen – so not a lot of scrolling needed.
You can also see that at the top of the screen is a tab marked Thesaurus. With a single hit, you can get a list of similar words to the one for which you’ve just found a definition. Very cool.
And for those of you who love your International Phonetic Alphabet, there’s even an option to see the pronunciation in IPA! Here’s what that looks like:
So although I use the full website only occasionally, it’s my most frequently used dictionary app. 
3. The Longman Dictionary of Contemporary English
Teachers of English as a foreign/second language will appreciate the LDOCE because of its “defining vocabulary,” which is the designated list of words lexicographers use to write dictionary definitions. The LDOCE uses a 2,000 word list, which is one of the smallest I’ve come across. The definitions, therefore, are very simple although sometimes too simple if you are looking for more detail.
Like the Macmillan, the Longman also marks word frequencies in terms of written and spoken frequencies. So want scores as being in the top 1000 written words and top 1000 spoken, whereas aspire doesn’t score at all.
An honorary mention goes to the Oxford Advanced American Dictionary for Learners of English and the Oxford Advanced Learners Dictionary for non-US learners. Both use a 3000-word defining dictionary (the Oxford 3000™) and so provide simplified definitions for words.
2. The Merriam-Webster
When the American lexicographer Noah Webster died in 1843, G. & C. Merriam & Co. acquired the rights to his popular American Dictionary of the English Language. The M-W dictionary is probably as American a dictionary in the US as the Oxford is outside of the US. It is based on the print version of Merriam-Webster’s Collegiate® Dictionary, Eleventh Edition and is clearly geared toward American English. It includes etymologies, parts-of-speech, and pronunciations.
For a fee (currently $29.95 per year), you can “upgrade” to the more detailed Unabridged dictionary, which offers more words, more etymologies, and more examples/quotations. However, unless you’re a serious word nerd, the free M-W is a great choice for US users. There’s also an app available that comes in both free and paid versions.
1. The Oxford English Dictionary (OED)
If you just want a quick definition of a word, this is not the one the use, but if you want to really know and understand a specific word in all its glory and history, you can lose yourself in the OED. It is possible to get free access to this compendious resource from public libraries in the UK, and universities throughout the world. Although I am not on faculty at my local college, I can be a member of the library and therefore have full and free access to the OED just like any other student, so it really is worth trying to join your local college library. Otherwise, it’s $29.95 a month or $295.00 a year for a private subscription – pretty steep! 
Price aside, this is THE dictionary, even if you are using other versions of English than British English. The OED gives you a complete history of a word, including all its different meanings, along with citations from world literature. The etymologies can be an essay in themselves, and there are advanced search facilities that let you do all sorts of fancy analyses – truly a word nerd’s wet dream.
So there you have it. A septenary of recommendations for the lexically minded. Don’t forget to let us know if you have others that you think we’re missing. Happy word searching!
 It’s deliciously ironic that in a post ostensible about words and language that I get the opportunity to break a popular grammatical rule; namely, “Thou shalt not end a sentence with a preposition.” To be honest, I recommend sticking to that advice, and I frequently take it to heart when writing. However, the phrase, “…where do you turn to?” actually seems to flow better than “..to where do you turn?” I suppose you might argue that, “…where do you turn?” might be even better, with the final “to” being superfluous – and you might be right. However, if you find yourself in a situation where having a preposition at the end sounds better than the re-worked version without it there, take a deep breath and break the rule.
 I have heard that some school-based administrators block access to the Urban Dictionary precisely because of its level of profanity. I await the study that supports the hypothesis that banning access in school to the Urban Dictionary reduces the amount of profanity a kid uses. I’d be more inclined to use it as a teaching tool for word-formation and statistics – but then again I’d probably be sacked on my first day!
 UK readers may be familiar with the provocative, controversial, and viciously satirical comic called Viz, which has been in existence since 1979. One of the characters, Roger Mellie (the Man on the Telly) is the “author” of something called Roger’s Profanisaurus, which was first published in 1988 and strikes me as an early version of the Urban Dictionary.
 The premium version is, at the time of writing, a paltry $1.99 for Android devices and $2.99 for iOS. I can’t imagine why anyone wouldn’t give up less than the price of one cup of coffee for this dictionary! Even the Blackberry version is only $2.99, so go ahead and treat yourself.
 There is another way to access the OED, and that’s to buy the book – or books! My wife bought me the 20-volume 2nd Edition in print for a birthday present and that’s a thrill for any word nerd. The lowest price I could find online was for $800, so you may have to save your pennies ;) But seeing as this is probably the last time the OED will ever be printed, it’s also an investment in history. Well, that’s one excuse you can try.