Kinnara is the name of a group of demi-gods in the heaven.
They are called so due to their resembblence with humans ( naras) . They are, like the Gandharva race, good at music. Many puranas mentioned Kinnaras as follwers of Indra in his wars against the demons. In Mahaabhaaratham too, this race is mentioned many times.
The often mentioned demi-god groups are Rudras,Maruths, Aadithyas, Vasus, Siddhas, Saadhyas, Gandharvas, Garudas, Nagas, Kinnaras, Kimpurushas, Vidyaadharas, Yakshas or Guhyakas etc. Some groups have a fixed number of entities in them. For example, Rudras are eleven in number, Aadithyas are twelve, Maruths are seven and the like.