1. A child whose parents ain't married
2. A way to insult someone without swearing

A phrase to describe someone who is cognitively degenerating. Synonym of "going off the deep end". Can have varying degrees of severity.

Reference to the song "Hey You" by Pink Floyd. The line "and the worms ate into his brain" makes no sense in an otherwise linear and literal narration throughout the lyrics.

Besides the usual usages of a child born out of wedlock and a suitable name for someone you don’t like, there are other meanings as well. At one time it was used to refer to a hybrid device or one adapted from one purpose to another; in 1517 it was used to refer to second rate Spanish Sack wines and in engineering it refers to a type of coarse-toothed file.

A term used to describe someone who disregards other people in pursuit of their own self-interest. Usually includes the acts or act of lying, spreading mis-information, covering one's own ass at the expense of others, or employing other forms of bullshitting.

One born without married parents.

Besides all the usual meanings, it has a meaning in engineering as well. A bastard is a type of coarse-toothed file.

Those responsible for the death of Kenny on South Park.