Wordnet 3.0
NOUN (2)
1. 
 a member of the mixed Dravidian and Caucasian people of southern India and Sri Lanka; 
2. 
 the Dravidian language spoken since prehistoric times by the Tamil in southern India and Sri Lanka; 
ADJECTIVE (1)
1. 
 of or relating to a speaker of the Tamil language or the language itself; 
- Example: "Tamil agglutinative phrases"
The Collaborative International Dictionary of English v.0.48:
Tamil \Ta"mil\, a.
   Of or pertaining to the Tamils, or to their language.
   [Written also Tamul.]
   [1913 Webster]
The Collaborative International Dictionary of English v.0.48:
Tamil \Ta"mil\, n. [Written also Tamul.]
   1. (Ethnol.) One of a Dravidian race of men native of
      Northern Ceylon and Southern India.
      [1913 Webster]
   2. The Tamil language, the most important of the Dravidian
      languages. See Dravidian, a.
      [1913 Webster]
WordNet (r) 3.0 (2006):
Tamil
    adj 1: of or relating to a speaker of the Tamil language or the
           language itself; "Tamil agglutinative phrases"
    n 1: a member of the mixed Dravidian and Caucasian people of
         southern India and Sri Lanka
    2: the Dravidian language spoken since prehistoric times by the
       Tamil in southern India and Sri Lanka