Is Siamese supposed to be capitalized in a sentence?

"Siamese" is capitalized when it refers to the specific breed of cat (e.g., "My cat is a Siamese.").

However, it's not capitalized when used as a general adjective referring to something from Siam (Thailand) (e.g., "Siamese twins" or "Siamese fighting fish").

Here's a breakdown:

* Capitalized: "I have a Siamese cat." (referring to the breed)

* Not capitalized: "The twins were joined at the hip, like Siamese twins." (referring to a general concept)