What does illegitimate mean?

Answer 1

it means that it is unlawful, many years ago when a child was born to a woman who was not married, the child was called an "illigitimate child" this had such shame attached to it that during the 70's this term was done away with.

Answer 2

Illegitimacy is the state of being illegitimate, which means; not lawfully begotten; born out of wedlock; contrary to law of accepted forms of use; irregular; improper; illogical; contrary to logic; unsound.