Quick Definition
I overpower, quell, treat harshly
Strong's Definition
to exercise dominion against, i.e. oppress
Derivation: from G2596 (κατά) and a derivative of G1413 (δυνάστης);
KJV Usage: oppress
Thayer's Greek Lexicon
καταδυναστεύω; present passive participle καταδυναστευόμενος; the Sept. for δεπΘδ, ςΘωΗΡχ, etc.; with the genitive of person (Winers Grammar, 206 (193); Buttmann, 169 (147)), to exercise harsh control over one, to use one's power against one: Jas_2:6 (not Tdf. (see below)) (Diodorus 13, 73); τινα, to oppress one (Xenophon, conv. 5, 8; often in the Sept.). Jas_2:6 Tdf.; passive Act_10:38.
STRONGS NT 2616a: κατάθεμακατάθεμα, καταθεματος, τό, equivalent to κατανάθεμα(which see), of which it seems to be a vulgar corruption by syncope (cf. Koumanoudes, συναγωγή λέξεων ἀθησαυρων κτλ., under the word κατας); a curse; by metonymy, worthy of execration, an accursed thing: Rev_22:3 (Rec. κατανάθεμα; cf. Justin Martyr, quaest. et resp. 121, at the end; 'Teaching' 16, 5 [ET]). Not found in secular authors.
Mounce Concise Greek Dictionary
καταδυναστεύω katadynasteuō 2x
to tyrannize over, oppress, exploit, Act_10:38 ; Jas_2:6
Abbott-Smith Greek Lexicon
κατα -δυναστεύω ,
[in LXX for H3238 , H6231 , etc.;]
to exercise power over, oppress: c . acc pers . ( Xen .; LXX , Mic_2:2 , Wis_2:10 , al .); c . gen . pers ., Jas_2:6 (ὑμᾶς , T ); pass ., Act_10:38 ( cf. MM , Exp., xv).†
Moulton & Milligan — Vocabulary of the Greek NT
καταδυναστεύω [page 326]
The rather generalized use of this verb in Act_10:38 is illustrated by P Petr III. 36 ( a ) verso .2 (Ptol.) πολλάκ [ις ] σοι γέγραφα διότι καταδεδυνάστευᵒμαι ( sic the writer wished to change the tense) ἐν τῆι θυλ [α ]κῆι λιμῶι παραπολλύμενος , I have often explained to you in writing why I am being harshly treated in the prison, perishing from hunger : though the agent in Acts l.c. is the devil, the reference is to the physical sufferings attributed to possession.
For the verb of men in authority misusing their power, as in Jas_2:6 (cf. Wis_2:10 ; Wis_15:14 ; Wis_17:2 ), see also P Oxy I. 67 .15 (A.D. 338) where, in a dispute concerning property, the petitioner complains καταδυναστεύοντες ἐπέχουσιν τῶν ἡμῖν διαφερόντων οἰκοπέ [δω ]ν , certain persons are oppressing me and occupying my own estates.
Liddell-Scott — Intermediate Greek Lexicon
καταδυναστεύω fut. σω "to exercise power over", Xen.
STEPBible — Tyndale Abridged Greek Lexicon
κατα-δυναστεύω
[in LXX for יָנָה, עָשַׁק, etc. ;]
to exercise power over, oppress: with accusative of person(s) (Xen.; LXX, Mic.2:2, Wis.2:10, al.); with genitive of person(s), Jas.2:6 (ὑμᾶς, T); pass., Act.10:38 (cf. MM, Exp., xv).†
(AS)