Whether you are learning a second or third language or even improving your native language, you should have a dictionary. Yes, of course,there are dictionaries online, but what about when you're not next to the computer? What about when the power goes out or when your computer is broken or is being used by someone else in your household?

While most households have a computer, most of them only have one, so it wouldn't be surprising to find the need for printed reference material.

1. You can check your spelling.

With a dictionary you can look up words and make sure they are spelled correctly as you check their meanings. Even native speakers make mistakes especially with words that include double letters or multiple vowel combinations. Is it sensible or sensable, dependable or dependible, they're, their, or there, matterial or material, written or writen? With a dictionary you can know for sure. Computer spell checkers are limited to words. As long as the word exists in that form it is accepted. Spell checkers don't check meaning so if you use their when you need they're you are out of luck with the spell checker.

2. You can check the definitions of words to make sure you understood correctly.

Many words in English as well as in other languages have multiple definitions. How many meanings can you think of for get? While it is likely that you know the word you might be understanding it in a different definition than the writer intended.

3. You can learn new words.

Perhaps you know every word that exists in the English language, but I don't and you're probably the only one who does! To tell the truth most of us only use a few words on a daily basis and we only understand a few hundred or a few thousand more depending on how much we read and how difficult what we read it. I don't think a college education will necessarily improve your vocabulary more than temporarily. If you don't believe me, try to list 30 words you learned in the first course you took and give me at least one definition for each. I bet you can't do it in less than one hour if at all.
By having a dictionary, you can look up the meaning of new words and those words that you have forgotten.

4. You can learn how to pronounce a word that you may have only read.

It has happened to me many times. I have read a word, and I understood it in context, but then when speaking I have no idea how to pronounce it. Let's face it, English is not an easy language to pronounce especially British dialects. Most dictionaries will give you a phonetic guide with a key in the front to show you how to use it. If there is more than one pronunciation, they both will probably appear.
How do you pronounce interest or clematis? Most Spanish speakers will pronounce interest by dividing it into three syllables but most native speakers divide it only into two.
My mom says clem-A-tis whereas I saw it pronounced CLEM-a-tis on a gardening show.

5. You can use the grammatical notes to help you write.
If you are a second language speaker of English, a dictionary is essential. You should have one in your office and one at home. Good dictionaries have extra symbols to help you write correctly. Is it an adverb, adjective, noun, verb, pronoun, preposition, etc? The dictionary will tell you, and some dictionaries, like Longman,will often give you example sentences.
A common mistake made by second languge speakers of English is the omission of objects, when they are needed, and the inclusion of objects when they are not. For example: I gave to him. We are missing the 'it'. I gave it to him. Why do we need 'it'? Well, we need it because give is a transitive verb. Transitive verbs need objects whereas Intransitive verbs don't. Dictionaries will tell you when a verb or a definition of a verb is transitive or not, so the dictionary becomes essential when proofreading your reports.
Some dictionaries, like Webster, will show transitive verbs as VT, and intransitive verbs as VI. Be careful! Some verbs are both transitive and intransitive depending on the definition, so check the definition you are using to verify.

6. You can learn phrasal verbs.

Phrasal verbs are difficult to learn as a second language and you can often have multiple combinations. A phrasal verb is typically a verb + a preposition with a different meaning from the verb by itself. The plane took off at 8 this morning, uses the phrasal verb 'take off'. The meaning of 'take off' is not the same as take + off.
English has hundreds if not thousands of them. Many dictionaries for learners will include phrasal verbs. These are typically the more expensive, larger versions. Typically they say something on the cover saying it is for second language speakers. I saw a nice one by Longman.

If you have a dictionary, but it is old, consider buying a new one. Words are added to English dictionaries every year, so if your dictionary was from when you were in elementary school, you will be missing many technological words that you can find in a new dictionary.

If you are going to be speaking with Americans, then I suggest getting a Webster or American Heritage dictionary. If you are learning English as a second language and need many examples, then consider getting a Longman dictionary, or one of the others in a version for learners. If you are going to be speaking primarily with British English speakers, get an Oxford dictionary.

If you have a very low level consider buying a picture dictionary.

American English:



Webster's New World College Dictionary, Fourth Edition (Book with CD-ROM)



Longman Dictionary of American English with Thesaurus and CD-ROM (New Edition)



The American Heritage Dictionary of the English Language, Fourth Edition



The American Heritage Student Dictionary

Other dictionaries: