A good vocabulary study program includes more than just memorizing a word and its definition. You need to make sure that you know exactly how to pronounce the word, and how to use it correctly in a sentence. You’ll have to practice spelling the word so that you don’t make any errors when you use it in a written document. And if you want to get the most out of a word, you’ll include some research into its synonyms and antonyms, and also look into the history of the word (its etymology). This last step is crucial to helping you distinguish the subtle differences between words that appear to be related, but really aren’t.

A good example of this is the difference between words that start with the prefix dis- and words that start with the prefix dys-. While many of the words beginning with these two prefixes do have the same general sense of something negative, the roots of these prefixes are from two different languages, and have two different meanings. Dis- is an Old Latin word form that adds the meaning of “opposite of” or “lack of” to a word, and dys- is an Old Greek root word meaning “abnormal” or “bad.” Here are some examples of how each of these prefixes are used:

dystopia
The English philosopher Thomas More wrote a book titled “Utopia” in which he described a perfect world where equality, justice, and peace reigned supreme. Three hundred years later, another author added the negative prefix to create a word describing a world in which the opposite holds true. The Merriam-Webster online dictionary notes that this was the most searched-for word the week of the release of the movie “The Hunger Games.”

dysfunction
Here we see a good example of the difference between the two prefixes. You might think that the negative version of “to function” is “to not function,” but instead this word means “functioning, but not correctly.”

disobedient
In this case, with the use of the prefix dis-, we do have a word where the negative meaning is “not [obedient].”

disaster
Sometimes the meaning of a word isn’t as easy to see; unlike the two previous words, where the prefixes were attached to recognizable words (“function” and “obedient”) and obviously negating them, if you tried to break this word apart in the same way, you might think it means “not a purple flower.” Etymology comes to the rescue again, and when you look up this word you’ll see that the second half of the word comes from the Latin word astro, meaning “star.” It was long believed that the stars governed our fates, so if the stars were opposing you, you’d have bad luck and terrible things would happen – in other words, disasters.

Remember, a disciplined student of English vocabulary is generally disinclined to discard any tools that can help them get ahead, so keep word research in your study plan!