What is a bastard?

Answer 1

It often means you were born when you're mum and dad weren't married.

The word bastard has a number of meanings. It originates from Latin/Greek word berstardium, and it means "the man who has no father as his mother was unmarried at the time of his birth." The original meaning was "to be born of unmarried parents." So a bastard is someone who was born before their parents were married (and, more commonly, someone who is unsure about who his mother/and or father were).

The word bastard also means a disagreeable, obnoxious person, something of doubtful origin, or a medium rough, cross-cut file (tool). It has become a general term of abuse now, and the original, literal meaning is rarely used.

Answer 2

A bastardizer is a person who bastardizes - who claims something or someone is illegitimate, or to reduce something from a higher to a lower state.