English translation (word)
English translation (etymon)
Ἔγκατα: Τὰ ἔντερα· ἀπὸ τοῦ ἐγκατέχειν τὴν τροφήν· λέγει δὲ τὸ ἧπαρ, καὶ τὸν σπλῆνα, καὶ τὰ περὶ τὸν πνεύμονα. Ἔντερον δὲ, οὐκ ἔγκατον. Τὸ δὲ ἔντερον, οἷον ἕτερον καὶ οὐχ ὅμοιον· ἢ παρὰ τὸ ἐντὸς κεῖσθαι τῶν μελῶν
Enkata "entrails": from the fact that they retain food in themselves. This applies to what is next to the liver, the spleen and the lung. But the intestine (enteron) is not an entrail: the intestine is as though it were 'the other one' (heteron), not similar; or it comes from the fact that they lie (keisthai) inside (entos) the body
If the last clause refers to ἔγκατα and not to ἔντερον, the word is derived from ἔγκειμαι, here decomposed as ἐντὸς κεῖσθαι. This is a descriptive etymology defining the entrails by reference to their position. The etymology is of the acrophonic type and keeps only the beginning of ἔγκειμαι, adding then the suffix -ατα which was well identified by Greek etymologists.
Etym. Symeonis, epsilon 27 Baldi (idem); Ps.-Zonaras, Lexicon, epsilon, p. 603 (idem)
On the etymological and semantic study, see J.-L. Perpillou and Ch. de Lamberterie, Revue de Philologie 72, 1998, 247-257.