The Collaborative International Dictionary of English v.0.48:

Indochinese \In`do*chi*nese"\, Indo-Chinese \In`do-Chi*nese"\,
   prop. a. [Indo- + Chinese.]
   1. Of or pertaining to Indo-China (i. e., Farther India, or
      India beyond the Ganges).
      [1913 Webster]

   2. Of or pert. to the Mongoloid races of India, esp. Farther
      India, or designating, or of, their languages.

            Tradition and comparative philology agree in
            pointing to northwestern China, between the upper
            courses of the Yang-tsekiang and of the Ho-ang-ho,
            as the original home of the Indo-Chinese race.
                                                  --Census of
                                                  India, 1901.
      [Webster 1913 Suppl.]