IPA: /ˌmʌltiˈpɑːrti/
KK: /mʌltiˈpɑrti/
Relating to or involving more than two political groups or parties.
The multiparty system allows for a greater diversity of political opinions.
Multiparty → It is formed from "multi-" (meaning many) and "party" (from Old French *partie*, meaning a part or division). The word "multiparty" refers to a system or situation involving many parties or groups.
Think of 'many' ('multi-') groups or 'parts' ('party') coming together — that's what multiparty means.
No commonly confused words.