Siamese twin

 Longman Dictionary of Contemporary English 5++朗文当代英语 5++LDOCE 5++朗文 5++ˌSiamese ˈtwin noun [countable usually plural]  TWOone of two people who are born joined to each other – sometimes considered offensive 连体双胞胎，暹罗孪生子〔有时被认为具有冒犯性〕 SYN conjoined twin

Examples from the Corpus

Siamese twin• Eileen Delaney has five cats in all ... including Pickle's Siamese twin Branston.Origin Siamese twin (1800-1900) From such a pair (Chang and Eng) who were born in Siam (now Thailand)

ˌSiamese ˈtwin nounChineseSyllable  

people two born are who Corpus one of

Siamese twin
ˌSiamese ˈtwin noun [countable usually plural]one of two people who are born joined to each other – sometimes considered offensive
   SYN  conjoined twin

Siamese twinBrE /ˌsaɪəmiːz ˈtwɪn/ 🔊NAmE /ˌsaɪəmiːz ˈtwɪn/ 🔊 noun = conjoined twin