fix, (e-)stablish, stedfastly set, strengthen

Strong’s Dictionary of Greek Words:

Number:
4741 (find all occurrences in KJV Bible)
Greek:
στηρίζω
Transliteration:
sterizo
Phonic:
stay-rid’-zo
Meaning:
from a presumed derivative of 2476 (like 4731); to set fast, i.e. (literally) to turn resolutely in a certain direction, or (figuratively) to confirm
KJV Usage:
fix, (e-)stablish, stedfastly set, strengthen