illegitimate has definitions from the field of law
1
[ adjective ] (law) contrary to or forbidden by law

Examples

"an illegitimate seizure of power" "illicit trade" "an outlaw strike" "unlawful measures"

Used in print

(John Hazard Wildman, "Take It Off," The Arizona...)

This nettled the children into the revelation of exact truth , a sacrifice of their secret superiority over grown people , but a victory in the wide fields of perpetration and illegitimate accomplishment .

Related terms

illegal

2
[ adjective ] of marriages and offspring; not recognized as lawful
3
[ noun ] the illegitimate offspring of unmarried parents

Related terms

offspring bastardize

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