The term 'Siamese' refers to a breed of CAT that originated in Thailand, formerly known as Siam. The crossword solutions for this term are 'THAI' (4 letters), 'TAI' (3 letters), 'CAT' (3 letters), and 'Thais' (5 letters). 'THAI' is the name of the country where the Siamese CAT originated, while 'TAI' is an ethnic group native to the region. 'CAT' is a reference to the breed itself, and 'Thais' is the plural form of 'THAI'.