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ef-

American  
  1. variant of ex- (by assimilation) before f: efficient.


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.

“It’s about seeing the digestive system as one of the performance factors,” says EF Pro Cycling’s Carceller.

From The Wall Street Journal • Apr. 28, 2026

Technically, it has shown standout relative strength against medical equipment peers, as the ratio chart versus the iShares medical device EF has trended higher all year.

From Barron's • Dec. 9, 2025

Teams from 10 different countries will be represented, while EF Education – Oatly and AG Insurance – Soudal will make their debut appearances.

From BBC • Apr. 24, 2025

The tornado is on the upper end of the lowest rating of the EF scale, according to Cohen.

From Los Angeles Times • Mar. 13, 2025

As a matter of fact, however, neither of these possibilities is actually realized and the regression line EF is approximated in an actual series of data.

From The Social Direction of Evolution An Outline of the Science of Eugenics by Kellicott, William E.

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