Calogero (from the Greek: καλόγερος, romanized: kalógeros, a familiar term for a monk) is common given name and family name, and a place name of Greek origin.^{[1][2][3][4][5]}

• (Masculine): Calocero
  • (Hypocoristic): Calò, Gero, Gerino
• Feminine: Calogera, Calocera

• Catalan: Calógero,^[6] Calogerio,^[6] Calocer^[6]
• English: Charles
• Ancient Greek: Καλόγερος (Kalogeros)^[5]
• Latin: Calogerus,^[2][4][5] Calocerus^[4]
• Polish: Kaloger
• Russian: Калогер (Kaloger)
• Sicilian: Calòjiru, Calòriju
• Spanish: Calógero,^[6] Calógerio,^[6] Calocero^[6]

Derived from the Ancient Greek: καλόγερος, romanized: kalogeros, composed of Ancient Greek: καλός, romanized: kalos (Ancient Greek "fair"; Modern Greek "good") and Ancient Greek: γέρων, romanized: geron ("old man", "old") and literally means "nice old man", "one who has nice old age"";^{[1][2][3][4][5][6][7]} the first element is reminiscent of such names as Calliope and Callimachus, while the second is reminiscent of the name Gerontius. A second interpretation, not generally accepted, is that the second element is the Greek keros (grain), according to which the name would mean "good grain".^{[7][dubious – discuss]}

Historically, in the ambit of Greek Orthodoxy, the term caloyer is used as a name for a monk or a hermit, in a manner that translates as "brother" or "monk",^[1][3][5][6] a significance that is retained in Modern Greek.

The name is traditionally found in and is characteristic of Sicily, bestowed by the cultus of Saint Calogerus the Anchorite, a monk and hermit near Sciacca;^[3][5][7] in the province of Agrigento, Calogero is the third-most widespread masculine name,^[8] but it is well-attested in all the rest of the island.

The feast day is celebrated on June 18 in honour of Saint Calogerus, exorcist and hermit in Sicily.^[7][9][10] Other feast dates recorded for the name are:

• February 11, Saint Calogerus, Bishop of Ravenna and confessor^[7]
• April 18, Saint Calocerus, Roman soldier and martyr at Albenga under Hadrian^[7][9]
• 19 May, Saint Calocerus the Eunuch, brother of Saint Parthenius, martyred under Decius, commemorated together with Parthenius^[6][7][9]

• Calogero (singer) (born 1971 in Échirolles as Calogero Joseph Salvatore Maurici), French singer-songwriter

• Calogero Bagarella (1935–1969), Italian criminal and member of the Sicilian Mafia
• Calogero "Jerry" Calà (born 1951), Italian comedian and filmmaker
• Calogero "Charly" Chiarelli (born 1948), Italian-Canadian writer, storyteller, actor and musician
• Calogero Conti (1924–2020), commonly referred to as "Zu Liddu", Sicilian mafioso
• Calogero Lo Giudice (1938–2021), Italian politician
• Calogero Minacore (1910–1993), also known as Carlos "The Little Man" Marcello, Italian-American mafioso who became the boss of the New Orléans crime family
• Calogero "Chazz" Palminteri (born 1952), American actor, screenwriter and producer; descended from immigrants from Agrigento, Sicily
• Calogero Pisano (born 1981), Italian politician
• Calogero Rizzuto (architect) (1955–2020), Italian architect and historic preservationist
• Calogero "Don Calò" Vizzini (1877–1954), historical Mafia boss of Villalba in the Italian province of Caltanissetta, Sicily

• Fiorenza Calogero (born 1978), Italian singer and actress
• Francesco Calogero (1935–2026), Italian physicist and peace activist
  • Calogero conjecture, minority interpretation of quantum mechanics (attributed to Francesco Calogero)
  • Calogero–Degasperis–Fokas equation, the nonlinear partial differential equation (jointly attributed to Francesco Calogero)
• Guido Calogero [it], Italian philosopher, thinker, activist, and Partito d'Azione politician
• Nicholas J. Calogero (1924–2004), American politician
• Pascal F. Calogero Jr. (1931–2018), American judge

• Calogero "C" Anello, the son / main character in A Bronx Tale^[11]
• Calogero "Clay" Appuzzo, a character in Showtime's drama I'm Dying Up Here, portrayed by Sebastian Stan
• Calogera "Al" Culcher, a personality in numerous comedy stylings of Aldo, Giovanni & Giacomo
• Calogero Sedara, a character in the romance Il Gattopardo by Giuseppe Tomasi di Lampedusa
• Calogero Di Spelta, a character in the comedy La grande magia by Eduardo De Filippo
• Calogero (called Calò), a character in The Godfather and The Godfather: Part III, portrayed by Franco Citti

• Albaigès i Olivart, Josep M. (1993). Diccionario de nombres de pers. ISBN 9788447502646.
• Burgio, Alfonso (1992). Dizionario dei nomi propri di persona. Roma: Hermes Edizioni. ISBN 88-7938-013-3.
• De Felice, Emidio (1978). Nomi d'Italia. Vol. 1. Milano: Arnoldo Mondadori Editore.
• Ferrari, Claudio Ermanno (1830). "Vocabolario de' nomi proprj sustantivi tanto d'uomini che di femmine". In Carrer, Luigi; Federici, Fortunato (eds.). Dizionario della lingua italiana (in Italian). Vol. 7. Padova: Tipografia della Minerva. pp. 571–732.
• Galgani, Fabio (2005). Onomastica Maremmana. Centro Studi Storici "A. Gabrielli".
• La Stella T., Enzo (2009). Santi e fanti - Dizionario dei nomi di persona. Bologna: Zanichelli. ISBN 978-88-08-06345-8.