fidelis

From fidēs (“faith, trust”) +‎ -ēlis.

• (Classical Latin) IPA^(key): [fɪˈdeː.lɪs]
• (modern Italianate Ecclesiastical) IPA^(key): [fiˈd̪ɛː.lis]

fidēlis (neuter fidēle, comparative fidēlior, superlative fidēlissimus, adverb fidēliter); third-declension two-termination adjective

1. faithful, loyal
   • semper fidelis
     • always faithful
   • 166 BCE, Publius Terentius Afer, Andria 459–460:

     MȲSĪS: Ita pol quidem rēs est, ut dīxtī, Lesbia! / Fidēlem haud fermē mulierī inveniās virum.

     MYSIS: By Pollux, the situation is just as you’ve said, Lesbia! Hardly ever will you find a man who’s faithful to a woman.

2. true, trustworthy, dependable
3. believing, trusting

Third-declension two-termination adjective.

fidēlis m (genitive fidēlis); third declension

1. a confidant, trustworthy person

Third-declension noun (i-stem).

• fidēlitās
• fīdō
• fīdus

• “fidelis”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• “fidelis”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• "fidelis", in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
• fidelis in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.