bona fides

noun bo·na fi·des \ˌbō-nə-ˈfī-ˌdēz, ÷ˈbō-nə-ˌfīdz\

Definition of bona fides

  1. 1 :  good faith :  sincerity

  2. 2 :  the fact of being genuine —often plural in construction

  3. 3 :  evidence of one's good faith or genuineness —often plural in construction

  4. 4 :  evidence of one's qualifications or achievements —often plural in construction

bona fides was our Word of the Day on 09/04/2010. Hear the podcast!

Did You Know?

Bona fides looks like a plural word in English, but in Latin, it's a singular noun that literally means "good faith." When bona fides entered English, it at first stayed very close to its Latin use - it was found mostly in legal contexts and it meant "honesty or lawfulness of purpose," just as it did in Latin. It also retained its singular construction. Using this original sense one might speak of "a claimant whose bona fides is unquestionable," for example. But in the 20th century, use of bona fides began to widen, and it began to appear with a plural verb in certain contexts. For example, a sentence such as "the informant's bona fides were ascertained" is now possible.

Origin and Etymology of bona fides

Latin, literally, good faith

First Known Use: 1665

BONA FIDES Defined for English Language Learners

bona fides

noun bo·na fi·des \ˌbō-nə-ˈfī-ˌdēz, ÷ˈbō-nə-ˌfīdz\

Definition of bona fides for English Language Learners

  • : evidence which shows that what you have said about yourself is true : evidence showing that you deserve a position or that you can be trusted

Law Dictionary

bona fides

noun bo·na fi·des \ˌbō-nə-ˈfī-ˌdēz, commonly ˈbō-nə-ˌfīdz\

Legal Definition of bona fides

  1. :  good faith the fact that the plaintiff conducted an investigation demonstrated its bona fidesJeannette Glass Co. v. Indemnity Ins. Co. of North America, 88 A.2d 407 (1952) (dissent)

Origin and Etymology of bona fides


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feeling or affected by lethargy

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