Meanings
- lawAgreements must be kept.First known use 19th c.
In the law of treaties, the most important manifestation of the principle of good faith is undoubtedly the rule of pacta sunt servanda.
2004, FA Engelen, Interpretation of Tax Treaties under International Law, page 1251 more example
Painstakingly negotiated agreements governed many aspects of international relations; the doctrine of pacta sunt servanda dictated that those agreements be obeyed.
2015, Susan Pedersen, ‘At least we worried’, London Review of Books, volume 37, number 12Synonyms: a promise is a promise
Synonyms & antonyms
phraseAgreements must be kept.
Origin
Latin plural of pactum (“pact”) + sunt servanda (“must be kept”), after pacta et promissa semperne servanda sint (“whether agreements and promises should always be kept”) in Cicero, De Oficiis 3.92.
Full word history & related roots →Cite this entry
pacta sunt servanda. (n.d.). In WatkinsX Dictionary. Retrieved November 5, 2026, from https://dictionary.watkinsx.com/word/pacta%20sunt%20servanda
“pacta sunt servanda.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/pacta%20sunt%20servanda. Accessed November 5, 2026.
WatkinsX Dictionary, s.v. “pacta sunt servanda,” accessed November 5, 2026, https://dictionary.watkinsx.com/word/pacta%20sunt%20servanda.
Source: pacta sunt servanda on Wiktionary, CC BY-SA 4.0.