Lexical Definition

‎κατηχέω‎ katēchéō (kat-ay-kheh'-o) to instruct G:V
from ‎κατά‎ and ‎ἦχος‎

inform, instruct, teach.

Usage: 7 forms in 8 verses
Form Translated As     In Verse(s)
κατηχοῦντι teaching Gal.6.6
κατηχούμενοσ being instructed Rom.2.18
being taught Gal.6.6
κατηχημένοσ instructed Acts.18.25
κατηχήσω I may instruct 1Cor.14.19
κατηχήθησαν They have been informed Acts.21.21
κατηχήθησ you were instructed Luke.1.4
κατήχηνται they have been informed Acts.21.24

Abbott-Smith

*† κατ-ηχέω, -ῶ,
1. to resound.
2. to teach by word of mouth, instruct, inform (v. Bl., Phil. Gosp., 20, 31): Ga 6:6; c. acc. pers., I Co 14:19; pass. c. acc. rei, Lk 1:4 (ICC, in l.), Ac 18:25 21:24 (cf. Lk 1:4), Ga 6:6; seq. ἐκ, c. gen. rei, Ro 2:18; περί, c. gen. pers., Ac 21:21.†

Abbott-Smith References

Book Refs
Luke 1:4
Acts 18:25 · 21:21 · 21:24
Romans 2:18
1 Corinthians 14:19
Galatians 6:6

Liddell-Scott-Jones

κατηχέω-έω,

sound over or through, ἁρμονία κ. τῆς θαλάττης [Refs 2nd c.AD+]

__2 sound amiss, opposed to συνηχέω, [Refs 1st c.BC+]
__II teach by word of mouth: hence generally, instruct, κ. τινὰ πολλὰ τῶν ἀγνοουμένων Agrippa 11 cited in [Refs 1st c.AD+]:—passive, to be informed or instructed, περί τινος [NT]; κ. ὅτι.. [κατηχέωήμεθα 2nd c.AD: Sextus Empiricus Philosophus “adversus Mathematicos” 5.5. ">Refs 1st c.AD+]
__II.2 in NT, instruct in the elements of religion, [NT]:—passive, περὶ ὧν κατηχέωήθης λόγων [κατηχέωούμενος τὸν λόγον NT.Gal.6.6; κατηχέωημένος τὴν ὁδὸν τοῦ Κυρίου NT.Acts.18.25, compare 3rd c.AD: Porphyrius Tyrius Philosophus “adversus Christianos - Abh. Berl. Akad.” 26. ">NT+3rd c.AD+]

LSJ Scripture Refs: Acts.21.211Cor.14.19Luke.1.4Gal.6.6Acts.18.25