We don't have synonyms for kafirs yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are kafir, kaffirs and kafiri.
(n) :
(Islam, countable, offensive, religious slur, politics) A disbeliever, a denier: someone who rejects or disbelieves in Allah or the tenets of Islam; or more broadly any non-Muslim.
(n) :
(Islam, countable, offensive, religious slur, politics) A disbeliever, a denier: someone who rejects or disbelieves in Allah or the tenets of Islam; or more broadly any non-Muslim.