The name Dionysius (; ''Dionū́sios'', "of Dionysus"; ) was common in classical and post-classical times. Etymologically it is a nominalized adjective formed with a -ios suffix from the stem Dionys- of the name of the Greek god, Dionysus, parallel to Apollon-ios from Apollon, with meanings of Dionysos' and Apollo's, etc. The exact beliefs attendant on the original assignment of such names remain unknown.

Regardless of the language of origin of Dionysos and Apollon, the -ios/-ius suffix is associated with a full range of endings of the first and second declension in the Greek and Latin languages. The names may thus appear in ancient writing in any of their cases. Dionysios itself refers only to males. The feminine version of the name is Dionysia, nominative case, in both Greek and Latin. The name of the plant and the festival, Dionysia, is the neuter plural nominative, which looks the same in English from both languages. Dionysiou is the masculine and neuter genitive case of the Greek second declension. Dionysias is not the -ios suffix.

Although in most cases transmuted, the name remains in many modern languages, such as English ''Dennis'' (''Denys'', ''Denis'', ''Denise''). The latter names have lost the suffix altogether, using Old French methods of marking the feminine, Denise. The modern Greek (closest to the original) is Dionysios or Dionysis. The Spanish is Dionisio. The Italian is Dionigi and last name, ''Dionisi''. Like Caesar in secular contexts, Dionysius sometimes became a title in religious contexts; for example, Dionysius was the episcopal title of the primates of Malankara Church (founded by Apostle Thomas in India) from 1765 until the amalgamation of that title with Catholicos of the East in 1934. Provided by Wikipedia

by Dionysius
Published 1708
prostant apud J. Goudge

by Dionysius
Published 1718
e typographæo Mariæ Matthews. Impensis W. Churchill, ad Insigne nigri Cygnis in vico Pater-Noster-Row

by Dionysius
Published 1726
typis Guil. Bowyer. Impensis J. & J. Knapton, R. Knaplock, J. & B. Sprint, D. Midwinter, G. & J. Innys, J. Osborn & T. Longman, & R. Robinson

by Dionysius
Published 1758
printed, and sold by the booksellers of London and Westminster

by Cato, Dionysius
Published 1735
Printed and sold by B. Franklin

by Lardner, Dionysius
Published 1850
Taylor, Walton, and Maberly

by Lardner, Dionysius
Published 1842

by Wijnpersse, Dionysius van de
Published 1796
Printed by William Young, bookseller, no. 52, Second-Street, corner of Chesnut-Street

by Huijsmans, Dionysius P
Published 1999
Springer-Verlag Berlin Heidelberg

by Hall, Samuel
Published 1837
J. Weale
Subjects: '; ...Lardner Dionysius / 1793-1859 / Steam engines / 1835...

by Browne, Patrick
Published 1789
Sold by B. White and Son
Other Authors: '; ...Ehret, Georg Dionysius...

Published 2005
Springer Berlin Heidelberg
Other Authors: '; ...Glycopantis, Dionysius...

by Hogg, Charles
Published 1765
Other Authors: '; ...Thomson, Dionysius...