והאומן אינו בונה אותה מדעת עצמו אלא דפתראות ופנקסאות יש לו לדעת היאך הוא עושה חדרים
"the master builder does not follow his own opinion, but has difteraot and pinkasaot - plans and descriptions [Jastrow's translation] to know how to arrange the chambers"
While both terms mean notebooks of paper now, they had different meanings in the times of the Talmud. As we noted, a diftera was a leather hide used for writing. A pinkas, on the other hand, was a board or tablet, usually coated in wax, upon which the words were engraved.
The word pinkas derives from the Greek pinax - also meaning "writing tablet".
Kutscher, in this online article, explains the connection between pinkas and פינג'ן finjan - "coffee-pot":
But while these Arabic words – and there are scores of others in this category – took the main road into Hebrew, through the agency of its revivers as a spoken vernacular in Israel, others came in other ways – with Arabic speaking Jews, or during the War of Independence. Keif (“fun,” “a good time”) seems to be an example of the first, findjan (“cup”) of the second. In the days before the State this word, which in Arabic means “coffee-pot,” apparently entered the language through contacts between soldiers serving in the Palmach and Arabs. However, some people insist that findjan, too belongs to the former category. Incidentally, this word has a most interesting history. It derives from the Greek pinax meaning “notebook” and also dish. It passed into Mishnaic Hebrew in the form of pinkas (“notebook”) and into Aramaic as pinkha (“plate”). Southern Iraq, where Aramaic was spoken, mostly under Persian rule, for over a thousand years, from before the time of Alexander the Great until after its conquest by the Arabs in the middle of the seventh century CE. Not surprisingly, many Aramaic words were absorbed by Persian. In modern Persia (Iran) an original k in certain circumstances becomes g, hence the forms ping and also pingan. From Persian it passed over, together with other words, into Arabic in which there is no p but only f. in literary Arabic g became dj, and hence the form findjan, which, by this circuitous route, came back to Israeli Hebrew. The original Greek pinax, accordingly, has three offsprings in Hebrew – pinkas, pinkha (which is rare), and findjan reflecting vicissitudes in the Near East over the past two thousand years. We may add that thanks to the Turks, who borrowed innumerable words from Arabic before they embarked upon their campaigns of conquest into Europe, the word is common in European, and especially Slavonic, languages. I knew it as a child in Hungary, the country of my birth. I did not dream that it existed in ancient Jewish literature, or that I should find it , in a different guise, when I settled in Israel.In his book Milim V'Toldoteihen, Kutscher writes that the Hungarian word was findzsa.
So while you might never have thought there was a connection between a pinax:
and a finjan:
and a pinkas:
now you know there is!