The Ghana international was expected to join fellow Ligue 1 side Rennes but opted for a move to Lorient instead.
The 23-year-old striker joined Trabzonspor from Valenciennes last season but failed to settle in and cement a regular place in the starting line-up.
Waris had a total of 19 caps for the Ghana national team and represented the Black Stars at the 2014 World Cup in Brazil.
The last time Waris played in France he scored nine times in 16 appearances for Valenciennes.
Waris had also attracted the interest of Premier League giants Manchester United. Trabzonspor President İbrahim Hacıosmanoğlu confirmed that United had been keeping tabs on Waris back in January.
“Lille were also interested in Waris before we signed him. However a player cannot play for three different clubs in one season so he will have to wait until the end of the season,” Hacıosmanoğlu was quoted as saying by the Express.
“We know Manchester United are monitoring him too.”
Waris joined Trabzonspor for £5 million this summer and has two goals and an assist in all competitions this season.
The highly rated Ghanian international joined Spartak Moscow in 2013 and spent last season on loan at Ligue 1 outfit Valenciennes.
Waris found the back of the net 10 times as well as providing five assists in 21 appearances for the Ligue 1 outfit.