Strong’s Greek
G1928 — epidiatassomai
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
ἐπιδιατάσσομαι
epidiatassomai — pronounced ep-ee-dee-ah-tas'-som-ahee
middle voice from 1909 and 1299; to appoint besides, i.e. supplement (as a codicil):--add to. see GREEK for 1909 see GREEK for 1299
1 occurrence in the KJV.
Galatians 3:15
Brethren, I speak after the manner of men; Though it be but a man’s covenant, yet if it be confirmed, no man disannulleth, or addeth thereto.