Aphedron is a Greek word for latrine

Latrine

A latrine is a communal facility containing one or more commonly many toilets which may be simple pit toilets or in the case of the United States Armed Forces any toilet including modern flush toilets...

.

Because the word occurs only once in the New Testament

New Testament

The New Testament is the second major division of the Christian biblical canon, the first such division being the much longer Old Testament....

 (Mark 7:19), and was unknown in classical texts, Martin Luther

Martin Luther

Martin Luther was a German priest, professor of theology and iconic figure of the Protestant Reformation. He strongly disputed the claim that freedom from God's punishment for sin could be purchased with money. He confronted indulgence salesman Johann Tetzel with his Ninety-Five Theses in 1517...

 translated the word as meaning the bowel. Likewise during the 19th Century various scholars assumed it was a euphemism

Euphemism

A euphemism is the substitution of a mild, inoffensive, relatively uncontroversial phrase for another more frank expression that might offend or otherwise suggest something unpleasant to the audience...

 for the human bowel.. However the discovery and publication of an inscription at Pergamon

Pergamon

Pergamon , or Pergamum, was an ancient Greek city in modern-day Turkey, in Mysia, today located from the Aegean Sea on a promontory on the north side of the river Caicus , that became the capital of the Kingdom of Pergamon during the Hellenistic period, under the Attalid dynasty, 281–133 BC...

confirmed that the word means latrine
Besides which the Mark 7:19 verse says "out into the afedron, cleaning all meats" which makes no sense if the meat is still lodged in the lower intestine.

Inscription

The following is a transcription and translation of the relevant text from Lex de astynomis Pergamenorum (Law of the town clerks of Pergamos).

483.220 ΑΦΕΔΡΩΝΩΝ = Concerning privies.

ΟΙ ΑΣΤΥΝΟΜΟΙ = the town clerks ΕΠΙΜΕΛΕΙΑΝ = care (f.acc.) ΠΟΙΕΙΣΘΩΣΑΝ = shall make ΤΩΝ ΤΕ = of the ΔΗΜΟΣΙΩΝ = public ΑΦΕΔΡΩΝΩΝ = privies, ΚΑΙ ΤΩΝ = and of ΕΞ ΑΥΤΩΝ = out of them ΥΠΟΝΟΜΩΝ = sewers pl. ΚΑΙ ΕΑΝ = and if ΤΙΝΕΣ = some ΜΗ ΣΤΕΓΝΟΙ = not covers/lids pl. ΥΠΑΡΧΩΣΙΝ = already in existence ΚΑΙ ΤΩΝ.... = and of (text broken)

Translation: Concerning WCs. The town clerks shall maintain the public WCs and their outpipes. And if some of them are not covered and of them... (text broken)