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What is a synonym?
A synonym is a word or phrase that means nearly the same thing as another word. Big and large are synonyms, and so are happy and glad. Few synonyms are perfect matches: they usually differ slightly in tone, formality, or the situations where they sound natural. Quick and rapid both mean fast, but rapid sounds more formal and technical, while quick fits everyday speech.
- happy → glad, pleased, content
- big → large, sizeable, substantial
- start → begin, commence, launch
What is an antonym?
An antonym is a word that means the opposite of another word. Hot and cold are antonyms, and so are open and closed. Some antonym pairs are absolute opposites with nothing in between, such as alive and dead. Others sit at opposite ends of a scale, such as hot and cold, where warm and cool sit in the middle.
- hot → cold
- open → closed
- arrive → depart
Synonym vs. antonym: the difference
A synonym points toward a similar meaning, while an antonym points toward the opposite one. The two ideas are usually taught together because the same word often has both: quick has synonyms like fast and rapid, and antonyms like slow and sluggish. Knowing a word's synonyms and antonyms at the same time gives a clearer picture of exactly where it sits on a scale of meaning.
How is a thesaurus different from a dictionary?
A dictionary explains what a word means. A thesaurus lists other words with a similar or opposite meaning, usually without defining any of them in detail. The two work well together: look up a word in the dictionary to check its exact meaning, then use a thesaurus to find alternatives once you know which shade of meaning you actually need.
How to choose the right synonym
Two synonyms are rarely fully interchangeable, so it helps to check three things before swapping one word for another: formality (angry versus irate), strength (annoyed versus furious), and the words it normally appears with (make a decision, not do a decision). Reading the word in an example sentence, rather than just scanning a word list, is usually the fastest way to tell whether a synonym actually fits.
Commonly looked-up synonyms
Look up any of these words to see its own synonyms and antonyms.
Frequently asked questions
What is a synonym?
A word or phrase that means nearly the same thing as another word, such as happy and glad, or big and large.
What is an antonym?
A word that means the opposite of another word, such as hot and cold, or open and closed.
What is the difference between a synonym and an antonym?
A synonym has a similar meaning to another word, while an antonym has the opposite meaning. Many words have both.
What is a thesaurus?
A reference tool that lists synonyms and antonyms for a word, usually without the detailed definitions a dictionary provides.
Are two synonyms ever exactly the same?
Rarely. Most synonyms differ slightly in formality, strength, or the words they are typically paired with, even when their core meaning is close.
Try it with a real collection
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