Siam

American

[sahy-am, sahy-am] / saɪˈæm, ˈsaɪ æm /

noun

former name of Thailand.
Gulf of, Thailand.

Siam British

/ ˈsaɪæm, saɪˈæm /

noun

the former name (until 1939 and 1945–49) of Thailand
an arm of the South China Sea between the Malay Peninsula and Indochina the former name of (the Gulf of) Thailand

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The 23-year-old Thai began the final day with a two-stroke lead and went on to clinch the top prize at the Siam Country Club Old Course in the coastal resort Pattaya.

From Barron's • Feb. 22, 2026

Tavatanakit had a three-round total of 16-under 200 on the Siam Country Club Old Course at Chonburi southeast of Bangkok.

From Seattle Times • Feb. 24, 2024

Hamas said that he was killed along with three other senior militants, including Ayman Siam, who Israel says was in charge of Hamas’ rocket-firing unit.

From Washington Times • Nov. 26, 2023

Named the world's most photographed place by Instagram in 2013, Siam Paragon is Thailand's most famous mall, drawing throngs of domestic and foreign shoppers daily to its high-end stores, aquarium, cinema and food court dining.

From Reuters • Oct. 4, 2023

The movie is loud, a full orchestra playing while Anna and the king of Siam twirl around and around a wide, shiny floor.

From "Things Not Seen" by Andrew Clements

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023