Strong’s Greek
G585 — apodeixis
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
ἀπόδειξις
apodeixis — pronounced ap-od'-ike-sis
from 584; manifestation:--demonstration. see GREEK for 584
1 occurrence in the KJV.
1 Corinthians 2:4
And my speech and my preaching was not with enticing words of man’s wisdom, but in demonstration of the Spirit and of power: