We don't have synonyms for gross-out yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are cross out, gross out and cross-out.
(n) :
Alternative form of gross out. [(informal, chiefly Canada, US) Something which sickens, causes distress, or appalls by reason of being disgusting, gory, or repulsive.]
(n) :
Alternative form of gross out. [(informal, chiefly Canada, US) Something which sickens, causes distress, or appalls by reason of being disgusting, gory, or repulsive.]