ἀκαρός

From LSJ

καὶ ἐχθροὶ τοῦ ἀνθρώπου οἱ οἰκιακοὶ αὐτοῦ → and a man's foes shall be they of his own household (Micah 7:6, Matthew 10:36)

Source

Spanish (DGE)

σημαίνει τὸν ἐγκέφαλον ἢ τὴν κεφαλήν EMα 617.

Frisk Etymological English

Grammatical information: m?
Meaning: σημαίνει τὸν ἐγκέφαλον η την κεφαλήν. EM 45, 13.
Origin: XX [etym. unknown]
Etymology: Cf. ἔγκαρος and ἴγκρος with the same meaning. So it seems ἐν and κὰρη head. It would be the only relatively certain instance of reduction of ἐν to ἀ- (Schulze KZ 29, 263f. = Kl. Schr. 358), but Nussbaum, Head and Horn 1986, 72f. remains sceptic, as one would rather expect for this old form *ἀκρος.
See also:

Frisk Etymology German

ἀκαρός: {akarós}
Meaning: σημαίνει τὸν ἐγκέφαλον ἢ τὴν κεφαλήν. EM 45, 13.
Etymology : Vgl. die gleichbedeutenden ἔγκαρος und ἴγκρος. Kann somit die schwache Form von ἐν enthalten (Schulze KZ 29, 263f. = Kl. Schr. 358).
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