Strong’s Greek
G1967 — epiousios
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
ἐπιούσιος
epiousios — pronounced ep-ee-oo'-see-os
perhaps from the same as 1966; tomorrow's; but more probably from 1909 and a derivative of the present participle feminine of 1510; for subsistence, i.e. needful:--daily. see GREEK for 1966 see GREEK for 1909 see GREEK for 1510
2 occurrences in the KJV.
Matthew 6:11
Give us this day our daily bread.
Luke 11:3
Give us day by day our daily bread.