mortal sin

American  

noun

Roman Catholic Church.

1. a willfully committed, serious transgression against the law of God, depriving the soul of divine grace.

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mortal sin British  

noun

1. Christianity a sin regarded as involving total loss of grace Compare venial sin

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Example Sentences

That would be considered a mortal sin by the vast majority of football fandom.

From BBC • Mar. 29, 2026

“Normally, I’m like, ‘I don’t want to do that,’” says Jackman, over Zoom from a New York hotel room, as if he’s confessing a mortal sin.

From Los Angeles Times • Nov. 19, 2025

Most of us have been taught from a young age that failing to stretch before or after exercising is akin to a mortal sin.

From Seattle Times • Dec. 26, 2022

Late-night talk show host James Corden apologized after he was accused of committing a mortal sin in the world of comedy: He stole another comic’s joke.

From Washington Times • Nov. 2, 2022

Bora now realized that he must either commit mortal sin and save the lady, or refuse to commit it and let her die.

From "The Once and Future King" by T. H. White