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Why you use a thesaurus

The main purpose of a thesaurus is to list words which have the same or similar meanings. These words are called synonyms. Knowing the synonyms for a word is a great help in expressing yourself better, in writing or in speech. For example, you can find another word to use instead of a word that is rather ordinary and is used too much; you can find a standard word for an informal word or expression or, alternatively, an informal word to use instead of a standard word.

The Macquarie Student Thesaurus provides many thousands of lists of synonyms. It also gives you a lot of other information – for example, how to use the words and their synonyms in sentences, words with related meanings, words with opposite meanings, labelling to show which words are informal, and so on. Following is some guidance on how all this information is set out.

How to find a word

See our Search help section.

Homograph numbers

Homographs are words that have the same spelling, but completely different meanings. Homographs are listed as separate headwords in the thesaurus. Each one has a raised number (superscript). For example, scrub1 with the meaning of `clean’ and scrub2 with the meaning of `bush’.

Parts of speech

The headword is followed by the part of speech (noun, verb, adjective, adverb, pronoun, conjunction, preposition and interjection) to show how the word is used in a sentence. So the part of speech for the word decisive is adjective, and for the word dinosaur is noun. There can be more than one part of speech, as in ditch, which is a noun and a verb.

Different senses

Most words have more than one sense (or meaning). If there is more than one sense, each sense is given a number. If there is only one sense, there is no number. So the examples decisive, dispense and ditch both have two meanings, while dinosaur has only one.


Sometimes a word or a particular sense of a word is used in a special phrase. The phrase is given in bold type, following the sense number if there is one. This shows that the sense that is being covered is that of the phrase, rather than of the headword alone. For example, look at dispense, sense 2, which covers the meaning of the phrase dispense with.

Example sentences

For each sense of the headword, there is an example sentence in italic type which follows directly after the number. The purpose of the example sentence is both to show the meaning clearly and also to show you how the word is used in a sentence.


The example sentence for each sense is followed by a small square icon and then a list of synonyms in bold type.  A synonym may not have exactly the same meaning as the headword (there are not many words with exactly the same meaning as another) but the synonyms which appear in this list are very similar in meaning and can be used in the same sample sentence in place of the headword. For example, look at decisive, sense 1. All the synonyms in bold type after the square icon can be used in the sample sentence `He led the troops to a decisive victory’ in place of the word `decisive’.

If a synonym has a slightly different meaning or cannot be used in the sentence because it needs a different grammatical construction, it is placed on a new line and has its own sample sentence or phrase in italic type. For example, look at decisive, sense 2, where the synonym decided is on a separate line with a sample sentence placing the synonym in a new context (because, although you can talk about a `decisive person’, you can’t talk about a `decided person’).

When a phrase is given before the example sentence, the following synonyms match the whole of the phrase, not just the headword. For example, look at dispense, sense 2, which covers the meaning of the phrase dispense with. All the synonyms given can be used in the example sentence in place of `dispense with’, not in place of `dispense’.

Extra information

After the synonyms for each sense, there may be one or more of the following types of extra information:

Vocabulary extension:  This includes synonyms that are at a more advanced level of vocabulary than the normal range of the thesaurus and are included for the benefit of students who want to explore a more difficult level of language.

Related: These are words which have a related meaning but are not close enough in meaning to be included as synonyms.

Opposite: These are words which have an opposite meaning, or a meaning which is very close to being opposite (antonyms).


Labels are used to show if there is anything special about a word or any restriction on when a word is used.  The most common label used in this thesaurus is informal. However, some words are labelled poetic to indicate that they are mainly used in literature or are rather old-fashioned.

Most usually the label (in italics and in parentheses) is placed after a synonym to show that the synonym is informal. However, sometimes the sense of the headword is itself informal, in which case the label appears before the example sentence for that sense.

For example, look at the verb sense of ditch (sense 2). The word ditch in this sense is itself informal as indicated by the label after the verb part of speech. However, some of its synonyms (discard and get rid of) are not informal and have no label; others (dump and scrap) are informal and so these two synonyms each have their own informal label.

Special lists

Another useful feature of the thesaurus is the provision of lists of types of certain things or items. A dog is a type of animal, not a synonym for animal; a thesaurus is a type of book, not a synonym for book. Therefore `dog’ does not appear as a synonym at the entry for animal, nor does `thesaurus’ appear as a synonym at book.

However, in your writing you may want to think of  specific examples of a thing and so the thesaurus provides such special lists in shaded boxes at the end of certain entries, such as animal and book. As an example, look at the entry for dinosaur in the sample entries display.


The final section of the thesaurus consists of an extensive alphabetical Index. Each page has a shaded strip down the edge so that you can quickly find the index section. As in the main part of the thesaurus, there is also a guide word at the top of the page to help you find which words are on that page.

As mentioned above, you can use the index as a way to finding the word you want rather than looking for it among the headwords. Of course, if you have found that your word is not a headword, this is particularly helpful.

For example, if the word you want to look up is decisive and you have decided to look in the index rather than the headwords, you will find that that decisive in the index has references to four headwords: conclusive, crucial, decisive and steady. The fact that decisive itself is one of the references tells you that decisive is a headword and has its own entry, so this will be the best one for you to look up first. Afterwards you may also like to look at the other headwords listed (conclusivecrucial, steady) to see if there are some more ideas there.

On the other hand, if the word you want to look up is pivotal, you will find references in the index to three headwords:  central, critical and decisive. This shows that pivotal does not have its own headword (which you will already know if you have looked for it among the headwords) but that it appears as a synonym at three other headwords. Just finding these references will give some ideas for alternative words for pivotal. To find more, choose the one that you think is closest to the meaning you have in mind and go to that headword where you will find more synonyms. For example, if you go to the headword decisive, you will find pivotal as one of the synonyms at sense 1 and so you then know that the other synonyms in the sense 1 list are also synonyms for pivotal.