Much attention has been paid to the mystery the book's title refers to. In fact, Eco has stated that his intention was to find a "totally neutral title". In one version of the story, when he had finished writing the novel, Eco hurriedly suggested some ten names for it and asked a few of his friends to choose one. They chose The Name of the Rose. In another version of the story, Eco had wanted the neutral title Adso of Melk, but that was vetoed by his publisher, and then the title The Name of the Rose "came to me virtually by chance."
The book's last line, "Stat rosa pristina nomine, nomina nuda tenemus" translates as: "the rose of old remains only in its name; we possess naked names." The general sense, as Eco pointed out, was that from the beauty of the past, now disappeared, we hold only the name. In this novel, the lost "rose" could be seen as Aristotle's book on comedy (now forever lost), the exquisite library now destroyed, or the beautiful peasant girl now dead. We only know them by the description Adso provides us — we only have the name of the book on comedy, not its contents. As Adso points out at the end of the fifth day, he does not even know the name of the peasant girl to lament her. Does this mean she does not endure at all?
This text has also been translated as "Yesterday's rose stands only in name, we hold only empty names". This line is a verse by twelfth century monk Bernard of Cluny (also known as Bernard of Morlaix). Medieval manuscripts of this line are not in agreement (but the best read "Roma" instead of "rosa"). Roma here introduces a "false" quantity, with a long-o for the Classical short-o; thus, a scribe may have written the "classically impeccable" rosa, which betrays the overall context and flexible prosody of Bernard. Eco quotes one Medieval variant verbatim, but Eco was not aware at the time of the text more commonly printed in modern editions, in which the reference is to Rome (Roma), not to a rose (rosa). The alternative text, with its context, runs: Nunc ubi Regulus aut ubi Romulus aut ubi Remus? / Stat Roma pristina nomine, nomina nuda tenemus. This translates as "Where now is Regulus, or Romulus, or Remus? / Primordial Rome abides only in its name; we hold only naked names". See the new excellent source edition of 2009: Bernard of Cluny, De contemptu mundi: Une vision du monde vers 1144, ed. and trans. A. Cresson, Témoins de notre histoire (Turnhout, 2009), p. 126 (bk. 1, 952), and note thereto p. 257.
Also the title of the book may be related to a poem by the Mexican poet and mystic Sor Juana Inés de la Cruz (1651–1695):
Rosa que al prado, encarnada, te ostentas presuntuosa de grana y carmín bañada: campa lozana y gustosa; pero no, que siendo hermosa también serás desdichada.
which appears in Eco's Postscript to the Name of the Rose, and is translated into English in "Note 1" of that book as:
Red rose growing in the meadow, you vaunt yourself bravely bathed in crimson and carmine: a rich and fragrant show. But no: Being fair, You will be unhappy soon.