Rainerius

Latin

Etymology

Derived from Proto-West Germanic *Raginahari — likely through Old Italian Rainerio — from Proto-Germanic *Raginaharjaz, derived from *raginą (“decision, advice, counsel”) +‎ *harjaz (“commander”).

Proper noun

Rainerius m sg (genitive Raineriī or Rainerī); second declension

1. (Medieval Latin) a male given name from Proto-West Germanic [in turn from Proto-Germanic]
   • 1265 August 11, Rainerio Scorcialupi, Trattato di pace fra i pisani e l'emiro di Tunisi [Peace treaty between the Pisan and the emir of Tunis]‎^[1] (overall work in Old Italian); collected in Ernesto Monaci, editor, Crestomazia italiana dei primi secoli, con prospetto delle inflessioni grammaticali e glossario, volume 1, Città di Castello: S. Lapi, 1889, page 167:

     Rainerius Scorcialupi notarius, scriba publicus Pisanorum […]

     Rainerius Scorcialupi, notary, public secretary of the Pisan […]

Declension

Second-declension noun, singular only.

	singular
nominative	Rainerius
genitive	Raineriī Rainerī1
dative	Raineriō
accusative	Rainerium
ablative	Raineriō
vocative	Rainerī

¹Found in older Latin (until the Augustan Age).