antipope
‘a person claiming to be or elected pope in opposition to the one chosen by church law’
Lexical development traced from the Tamil root:
E. antepope < Med.Lat. antipapa < Gk. anti ‘against, opposite, instead of’ + papa < papas ‘patriarch, bishop,’ ‘father,’ similar to pappa ‘o father,’ pappas ‘father,’ pappos ‘grandfather < pope < Tamil appā