αὐθεντέω
to have full power over
αὐθεντέω to act of oneself, i.e. (figuratively) dominate
Derivation: from a compound of G846 and an obsolete ἕντης (a worker);
KJV Usage: usurp authority over. G846
Thayer:
1) one who with his own hands kills another or himself
2) one who acts on his own authority, autocratic
3) an absolute master
4) to govern, exercise dominion over one

αὐθεντέω
authenteō
ow-then-teh'-o
From a compound of G846 and ἕντης hentēs (obsolete; a worker); to act of oneself, that is, (figuratively) dominate
KJV Usage: usurp authority over.