Planet: A self-gravitating body that is nearly round

The other day I was looking at the Sloan Digital Sky Survey (SDSS) database table on photometric classification. I needed to recall which type was a star and which was a galaxy. So I was interested to see the following two listings in this table buried deep in the SDSS information:

Galaxy: An extended object composed of many stars and other matter.

Star: A a self-luminous gaseous celestial body.

I guess I was just surprised at how pedantic it was.