Strong’s Greek
G845 — autoptes
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
αὐτόπτης
autoptes — pronounced ow-top'-tace
from 846 and 3700; self-seeing, i.e. an eye-witness:--eye-witness. see GREEK for 846 see GREEK for 3700
1 occurrence in the KJV.
Luke 1:2
Even as they delivered them unto us, which from the beginning were eyewitnesses, and ministers of the word;