fast
Fast (adj) means moving or able to move at high speed; quick. Example: “He's the fastest runner on the team.”
How to use fast
Learner’s notesIn plain EnglishQuick in speed, or firmly fixed — plus a separate, unrelated sense of deliberately not eating.
The "quick" sense and the "not eating" sense come from the same old root ("firm, secure") but are used completely differently today — don't assume a link in modern meaning.
Word forms
faster comparative, faster comparative, fasted past tense, fasts plural, Fasts plural, fasts plural, fasts singular, fastest superlative, fastest superlative
Fill the gap
Can you complete this real example?
They took the _____ train to save time.
Etymology
From Old English fæst, "firm, secure." The sense of "quick" developed later — the idea was that moving "fast" (firmly, steadily) toward something eventually came to mean moving rapidly, much as we still say "run hard" today.
Synonyms
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Related words
Rhymes for fast
See all rhymes for fast →Frequently asked questions
What does “fast” mean?
The word “fast” means moving or able to move at high speed; quick. In plain terms, quick in speed, or firmly fixed — plus a separate, unrelated sense of deliberately not eating.
How do you pronounce “fast”?
“Fast” is pronounced fahst (/fæst/ in IPA).
How do you use “fast” in a sentence?
Here is “fast” used in a sentence: “He's the fastest runner on the team.”
What is the opposite of “fast”?
The opposite of “fast” — its antonyms — is slow.
What part of speech is “fast”?
Depending on how it is used, “fast” can be an adjective, an adverb, a verb and a noun.
Where does the word “fast” come from?
The word “fast” comes from Old English.
Is “fast” a common word?
“Fast” is a very common word in modern English, usually learned at around the A1 level.
How many meanings does “fast” have?
“Fast” has 5 distinct senses listed in this dictionary. The most common is: moving or able to move at high speed; quick.
What is the difference between fast and quick?
Fast usually describes sustained high speed or motion, like a fast car or a fast runner. Quick emphasizes a short time taken to start or finish something, like a quick reply or a quick glance. A quick task is over rapidly; a fast object keeps moving at speed.
Is fast an adjective or an adverb?
Fast works as both. As an adjective it describes a noun — 'a fast train.' As an adverb it describes how an action happens — 'she runs fast.' Unlike many words, it does not add -ly, so 'fastly' is incorrect. The form stays the same in both roles.
What is the opposite of fast?
The opposite of fast is slow, meaning moving or happening at low speed. Related antonyms include sluggish, gradual, and unhurried, depending on the situation. For a slow-moving vehicle you might say slow or crawling; for a slow process, you could use leisurely or drawn-out.
What are the different meanings of fast?
Fast has more than one sense. Most often it means moving at high speed. It can also mean firmly fixed in place, as in 'hold fast' or 'fast asleep.' As a separate verb, to fast means to go without food, often for religious or health reasons. Context distinguishes them.
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Vocabulary lists that include fast: