online medical dictionary | definition of illegitimate

1. Not according to law; not regular or authorised; unlawful; improper.

2. Unlawfully begotten; born out of wedlock; bastard; as, an illegitimate child.

3. Not legitimately deduced or inferred; illogical; as, an illegitimate inference.

4. Not authorised by good usage; not genuine; spurious; as, an illegitimate word.

5. <botany> Illegitimate fertilization, or Illegitimate union, the fertilization of pistils by stamens not of their own length, in heterogonously dimorphic and trimorphic flowers.

(11 Mar 1998)