Greek side, Paok have signed Chupa Akpom for a second-time.
The former Arsenal striker left PAOK for Middlesbrough last summer.
He has now left the Riverside for a return to Greece.
“Boro striker Chuba Akpom has returned to Greece to link up with his former club PAOK on loan until the end of the season,” the Championship club announced.
“The 25-year-old joined Boro from the Greek Super League club 12 months ago and made an immediate impact, scoring twice in his first two games. He has totaled five in 40 appearances since arriving on Teesside and has figured just once this season.
“Chuba is returning to the club where he enjoyed the most successful period of his career – netting 18 goals in 79 appearances and playing a central role in PAOK’s first league title success for 34 years.
“The former Arsenal youngster was also a cup winner in Greece and helped PAOK to the brink of Champions League qualification.”