<p><strong>Noun:</strong></p><ul><li>Formerly Siam, a kingdom in SE Asia: official name of Siam 1939–45 and since 1949.</li><li>Area: 198,242 sq. mi. (513,445 sq. km).</li><li>Capital: Bangkok.</li><li>Gulf of Siam: an arm of the South China Sea, south of Thailand.</li></ul>