Emily Dickinson Lexicon

IL-LE-GIT'I-MATE, a. [See Legitimate.]

1. Unlawfully begotten; born out of wedlock; spurious; as, an illegitimate son or daughter.
2. Unlawful; contrary to law.
3. Not genuine; not of genuine origin; as, an illegitimate inference.
4. Not authorized by good usage; as, an illegitimate word.