Entry 3 senses · 2 variants Webster, 1913 Siamese /sīˌ-əm-ēz'/ · Si·a·mese · IPA /saɪ.əˈmiːz/ a. n. sing. & pl. 01 a. Of or pertaining to Siam, its native people, or their language. 1. Of or pertaining to Siam, its native people, or their language. 02 n. sing. & pl. A native or inhabitant of Siam; pl., the people of Siam. 1. A native or inhabitant of Siam; pl., the people of Siam. 2. The language of the Siamese.