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Synonyms

for certain

Idioms  

  1. Also, for sure. Without doubt. For example, I can't tell for certain if this is the right color, or I know for sure that she has a new car. The first term dates from the early 1300s. The variant, dating from the late 1500s, is also used colloquially to express agreement or assert the truth of a statement, as in Mary is really bossy.—That's for sure, or Are you coming to the party?—For sure I am.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

This finding suggests that compounds other than caffeine, such as polyphenols, may be responsible for certain cognitive benefits.

From Science Daily • May 3, 2026

What she knew for certain was that increased fuel costs were making her life much harder.

From Barron's • May 2, 2026

The Big Four accounting firm has been grappling with slower demand for certain advisory services and lower voluntary attrition.

From The Wall Street Journal • Apr. 30, 2026

In the 1950s, the Court under Warren began to tighten the rules for denaturalization on the grounds that using it as punishment for certain acts was cruel and inhuman.

From Salon • Apr. 26, 2026

She thought for certain it would have been illegal to say out loud.

From "A Place to Belong" by Cynthia Kadohata

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.