Using a Dictionary, Thesaurus, and Glossary

Reference questions are small decision problems. Each tool can help with words, but each answers a different kind of question. If you open the thesaurus when you really need a definition, a list of impressive-looking synonyms can lead you farther from the sentence’s meaning.

Which tool should you open first?

Start with the question you need answered. Use a dictionary to check meaning, spelling, pronunciation, or grammatical job. Use a thesaurus after you already understand the intended meaning and want alternatives. Use a glossary when a text uses a technical term in its own specialized way. For a word such as cell, a biology glossary may be more useful than the first general dictionary definition.

Why must every replacement return to the sentence?

Synonyms overlap; they are rarely interchangeable in every setting. A thesaurus may list slim, skinny, and slender together, yet their tone differs. After finding an alternative, check its definition, connotation, part of speech, and grammar in the original sentence. The reference source proposes; the sentence decides.

Watch: a focused video lesson

Epic Adventures in Third Grade With Mrs. Taylor teaches the exact skill this lesson develops. Watch for the decision you can reuse when you return to a full draft.

A four-step test-day routine

1. Name the information you need.
2. Choose the source built for that job.
3. Read the full entry, including labels and examples.
4. Return the result to the original sentence and verify the fit.

Practice

1. Which source tells whether advice is a noun or verb?
2. Which source is best for a technical term defined by a textbook?
3. Which source first suggests alternatives to important?
4. What should you do after selecting a synonym?
5. Why might the first dictionary definition be wrong for a sentence?
6. A glossary and dictionary disagree about a field-specific term. Which should guide that passage?

Answers and reasons

1. A dictionary.
2. The textbook’s glossary.
3. A thesaurus.
4. Check its definition, tone, grammar, and fit in the sentence.
5. Many words have multiple meanings; context selects the correct entry.
6. The glossary, because it defines how the document uses the specialized term.

Where this fits in your HiSET Writing plan

Use this lesson when a missed question points to the same decision. Continue with Commonly Confused Words and Contractions, Essential Spelling Rules, Suffixes and Word Families, or return to the HiSET Language Arts Study Center to choose your next Writing skill.

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