Brothers
Correction: Most likely this correct or at least in singular form, with the Plural form being "Adelphos" (Interesting Fact: Philadelphia is a latinization of the Greek phrase "Philos Adelphos" which means "Brotherly Love" or more literally "Love Brothers").
Though there is some theories that state that Adelphi comes from the word "Delphi", the name of a major Greek City. Delphi itself was most likely a variation of "Delphis" the Greek word for Dolphin.
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The word Adelphi (a + delphi) literally means "of the same womb." Dolphin and delphi are related in the sense that dolphin is the "womb fish," being a mammal.
The Adelphi was created in 1923.
The Adelphi ended in 1955.
Adelphi School was created in 1834.
Adelphi Whisky was created in 1826.
Adelphi Records was created in 1968.
Adelphi Papers was created in 1961.
Adelphi Edizioni was created in 1962.
Adelphi Academy was created in 1863.
Adelphi Mill was created in 1796.
Adelphi Films was created in 1939.
Dorothy Adelphi is 5' 2".
Little Theatre in the Adelphi ended in 1941.