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Synonyms

swear by

Idioms  
  1. Have great reliance on or confidence in, as in She swears by her personal physician . [Early 1800s]

  2. Also, swear to . Have reliable knowledge of, be sure of, as in I think she was going to the library but I can't swear to it . [Mid-1700s]

  3. Take an oath by, as in I swear by all the saints in heaven . [Early 1200s]


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.

Still possible: Some eclipse-chasers swear by the sea for the best chances at a clear view of the event.

From The Wall Street Journal • Mar. 27, 2026

“At the end of the day, the government is going to go with systems that have been deployed, where combatant commanders swear by the fact that they want one of what we have,” Mengucci said.

From Barron's • Jan. 15, 2026

Some people swear by writing a song every day and finishing it, even if it’s bad.

From Los Angeles Times • Dec. 1, 2025

All of these sports have their own history and methods; specific forms, procedures and even credos that those who take up the fight swear by.

From Salon • Oct. 4, 2025

“I swear by heaven, though now I must be shriven for doing so! Therefore come, let us go and together lose our sins.”

From "Ophelia" by Lisa Klein

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