Yhyacinthe Mewoli Abdon (born 18 October 1985 in Etoa) is a Cameroonian professional boxer.

[1] He competed in the lightweight event at the 2012 Summer Olympics and was eliminated in the round of 32 by Fazliddin Gaibnazarov.

[2] After his defeat, he was one of seven Cameroonian athletes who disappeared from the Olympic Village.

[3] He told media he wanted to stay in the UK to further his career.

[5] He turned pro in 2014, and began competing under name Abdon Cesar.