Strong’s Greek
G5398 — phoberos
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
φοβερός
phoberos — pronounced fob-er-os'
from 5401; frightful, i.e. (objectively) formidable:--fearful, terrible. see GREEK for 5401
3 occurrences in the KJV.
Hebrews 10:27
But a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries.
Hebrews 10:31
It is a fearful thing to fall into the hands of the living God.
Hebrews 12:21
And so terrible was the sight, that Moses said, I exceedingly fear and quake:)