The story
Stephanus (the surname of the writer of a famous early translation (in 1578) of the dialogues of the Ancient Greek philosopher Plato) + number (meaning page number)
Etymology from Wiktionary, CC BY-SA 4.0.
Stephanus number
Today it means: A standard reference number for a section of a given Platonic dialogue, referring to a page in the 1578 translation of Plato’s dialogues by Henricus Stephanus. Full definition →