The censored Basel edition of the Talmud was the archetype of such editions, as the censor erased or amended all those parts of the text he regarded as insulting to Christianity or various peoples, or as reflections of superstitious views.
The Basel censor, Father Marco Marino, first erased the forbidden word Talmud, replacing it by other terms, such as Gemarah or Shas, initials of Hebrew words for Six Orders.
Wherever the text used the word min (heretic, originally applied to Gnostic sects and only rarely to Christians), he changed it to read Sadducee or Epicurean.
All mention of Rome, even where reference was undoubtedly to the pagan Roman kingdom, was altered to read Aram (Mesopotamia) or Paras (Persia).
The words meshumad or mumar (convert) were also forbidden and amended.
A grave problem for all the censors was the word goy (gentile), which they always changed (sometimes puzzling scholars, who were unaware that the censor was responsible).
For a time the word goy was changed to akum (initials of "worshippers of stars"), but a convert informed the authorities that this term too constituted an affront to Christianity, since akum also denoted the initials of "worshipper of Christ and Mary."
It was therefore necessary to find substitutes, and the most common was the insertion of the word kuti (Samaritan) for goy.
In the Basel edition the censor ordered that the word kushi (African, Kushite) be inserted in place of goy.
Wherever the Talmud makes derogatory reference to Jesus or to Christianity in general, the comment was completely erased, and the name of Christ was systematically removed, even when the reference was not negative.
The Basel censor also decided to erase what he considered examples of personification of the Deity, as well as enigmatic legends.
In certain cases he added his own comments in the margin.
For example, where the text states that man comes into the world without sin, he added "According to the Christian belief, all men are born tainted with the sin of the first man."
Sections which he regarded as offending modesty were also eradicated, and other changes were made as well, as in the talmudic saying: "A man who has no wife cannot be called a man," which offended his sensibilities as a celibate monk.
He changed it to read "A Jew who has no wife…."
The Avodah Zarah tractate was not printed at all, since it deals with the holy days of non-Jews and relations with them.
Although the omissions and erasures were partially restored in other editions, there were always new censors in other countries who introduced new distortions and changes.
The Russian authorities, for example, decided that Greece could not be mentioned in the Talmud, since Russian culture was supposedly inspired by that of Greece, and the word was therefore altered wherever it appeared.
Some Russian censors declared that the phrase "Greek language" was offensive and changed it to read "language of akum."
The ignorance of many censors led to the misspelling of names, and many of the errors were perpetuated from edition to edition.
Some changes resulted from short-lived political calculations, such as the instruction of the Russian censor at the time of the Russo-Turkish War that the word goy be re-placed by Ishmael, a change which engendered a whole series of absurd errors.
The Talmud was not the sole work affected by the heavy hand of the censor, but because of its scope and range and the thousands of changes introduced over the centuries, it was impossible to correct all the mutilations even in editions published in countries free of censorship.
Offset printing perpetuated many of the mistakes and omissions, and only in the most recent editions have attempts been made to restore the original format of the text.
–Rabbi Adin Steinsaltz
From The Essential Talmud by Rabbi Adin Steinsaltz