Dispensation in the King James Version is translated from οικονομιαν. oikonomion.
https://biblehub.com/greek/3622.htm"3622. oikonomia, stewardship, administration
Usage: management of household affairs, stewardship, administration."
Look in the William Tyndale New Testament, for the four uses of oikonoma, The Tyndale New Testament was the first English translation from the Textus Receptus, whose verse wordings had a great influence upon the wordings of the Geneva Bible and the King James Version.
https://www.biblestudytools.com/tyn/1-corinthians/9.htmlI Corinthians 9: 17: "If I do it with a good will I have a rewarde. But yf I do it agaynst my will an office is committed vnto me." "Office" is the key word
Ephesians 1: 10: "to have it declared when the tyme were full come yt all thynges bothe ye thynges which are in heven and also the thynges which are in erthe shuld be gaddered togedder even in Christ:"
The Textus Receptus Greek says "for the oikonomian of the fullness of time to head up all things is Christ."
Ephesians 3: 2: " Yf ye have hearde of the ministracion (ministration) of the grace of god which is geven me to you warde."
Colossians 1: 25 "wher of I am made a minister acordynge to the ordinaunce of god which ordinaunce was geven me vnto you warde to fulfill ye worde of god."
"ordinaunce" is the key word.
The question is whether it can be determined where the King James Translators got their "dispensationalist" translation of oikonomian. One possibility is the John Wycliff English translation of the Latin Vulgate.
http://www.bibledbdata.org/onlinebibles/wycliffe_nt/I Corinthians 9: 17 "But if Y do this thing wilfuli, Y haue mede; but if ayens my wille, dispending is bitakun to me."
Ephesians 1: 10 "hym in the dispensacioun of plente of tymes to enstore alle thingis in Crist, whiche ben in heuenes, and whiche ben in erthe, in hym."
Ephesians 3: 2 " if netheles ye han herd the dispensacioun of Goddis grace, that is youun to me in you."
Colossians 1: 25 " Of which Y Poul am maad mynystre bi the dispensacioun of God, that is youun to me in you"
Now lets look at these same New Testament scriptures in the Geneva Bible.,
http://www.genevabible.org/files/Geneva_Bible/New_Testament/1Corinthians_F.pdfI Corinthians 9: 17 " For if I do it willingly, I have a
reward, but if I do it against my will, notwithstanding
the dispensation is committed unto me. "
Ephesians 1: 10: " That in the dispensation of the fullness of the times, he might
gather together in one all things, both which are in heaven, and which are in earth,
even in Christ."
Ephesians 3: 2 " If ye have heard of the dispensation of the grace of God, which is given me
toward you."
Colossians1: 25: " Whereof I am a minister, according to the dispensation of God, which is
given me towards you, to fulfill the word of God, "
The translation of oikonomia as dispensation first appeared in the Geneva Bible, and the King James Version followed that translation. But the John 1382 Wycliff English translation of Catholic Latin Bible of Jerome translated oikonomia as dispensation, in an older English version of the spelling, which is likely the source of that translation of oikonomia in the Geneva Bible.
It may have been the successor of John Calvin, Theodore Beza, who was responsible for changing the Tyndale translation of oikonomia to the older Catholic version of dispensation. Beza did some translations which had an influence upon the Committee which produced the Geneva Bible.
I Corinthians 9: 17