The 19-year-old joined the SPL outfit on loan until January 2021 in the summer transfer window following Leeds' promotion to the Premier League.
He made his debut in the first game of the season and scored his first of two league goals in October, having missed a chunk of the season due to injury.
Now, following 13 league appearances with Aberdeen, Edmondson returns to Leeds but may leave again on loan this month to join an EFL side.
He said today: "Would like to thank this amazing club and everyone within it to be given the opportunity to put on that shirt and represent this club.
"Was very special for me to have scored my first professional goals here and will always be remembered.
"Thank you all once again and I wish you all the best in the future."