We don't have synonyms for seviches yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are seiches, seviche and ceviches.
(n) :
Alternative spelling of ceviche. [(cooking) Raw seafood cured by marination in an acidic medium such as citrus, vinegar, or other souring agent, found primarily in Latin America.]
(n) :
Alternative spelling of ceviche. [(cooking) Raw seafood cured by marination in an acidic medium such as citrus, vinegar, or other souring agent, found primarily in Latin America.]