Siamese describes things connected to Siam, the old name for Thailand, a country in Southeast Asia. When you hear about Siamese cats, you're learning about an elegant breed with blue eyes and dark-colored faces, ears, and paws that originally came from this region. These cats were so treasured in ancient Siam that they were often kept by royalty and Buddhist monks.

The word appears in Siamese twins, an old-fashioned term for conjoined twins (people born physically connected to each other). This term came from Chang and Eng Bunker, famous conjoined twins born in Siam in 1811 who toured the world in the 1800s. Today, doctors and most people prefer saying conjoined twins instead, since it's more respectful and medically accurate.

You might also hear about Siamese fighting fish, also called bettas, which are small, colorful fish from Thailand known for their flowing fins. Male bettas are extremely territorial and may fight other males, which is how they got their name.

Since 1939, Siam has been called Thailand, so Siamese mostly appears in these specific phrases rather than in everyday conversation about the country itself.