What Does "Zero-day" Mean?
"Zero-day" is an English idiom, referring to a software vulnerability that is exploited by hackers before the software creator is aware of it, and before a patch has been released.Examples in Sentences
Here are three examples of the idiom "zero-day" used in a sentence:- A zero-day attack can be devastating since there's no defense in place.
- Software companies have reward programs for ethical hackers who find zero-day vulnerabilities.
- The company was hit by a zero-day exploit, compromising thousands of users' data.

What Is an Idiom?
An idiom is a commonly used expression whose meaning does not relate to the literal meaning of its words. In other words, if you were to translate "Zero-day" word for word, there is no guarantee the translation would help you to understand the meaning.An idiom often includes a cultural or historical context that makes it difficult for non-native English speakers to understand. A phrase is classified as an idiom when a direct translation of the words does not reveal the meaning. Most idioms rely on shared knowledge or experiences known only to a specific community.
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