Definitions of intelligent design used in the mainstream media are either so superficial as to be meaningless, or completely wrong in stating that ID is creationism and anti-evolutionary. One of the best basic definitions is from www.intelligentdesign.org:

The theory of intelligent design holds that certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection.

In his groundbreaking book, Signature in the Cell, Stephen Meyer expands on this definition and builds a strong, scientific case for the theory of intelligent design. Here is a short video of Meyer explaining his definition of ID as he used it in his book.