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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.

See Examples For:

To start things off, here are three personal-finance principles that I’ve come to swear by through my own wins and losses.

From MarketWatch Aug. 4, 2026

There’s a reason runners swear by pickle juice as a recovery drink, and why “pickle girls” have become their own corner of the internet.

From Salon May 28, 2026

Even those who swear by the broccoli concoction say they can’t be sure that they are benefiting from anything other than a placebo effect.

From The Wall Street Journal Feb. 12, 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

‘If you swear by your hope of Heaven and your fear of Hell never, never to mention any of this to anyone. Never tell my true name, nor that I have a cup.’

From "Johnny Tremain" by Esther Hoskins Forbes

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