undue

From un- +‎ due

• (Received Pronunciation) IPA^(key): /ʌnˈdjuː/
• (US) IPA^(key): /ʌnˈduː/, /ʌnˈdjuː/
• Rhymes: -uː
• Homophone: undo

undue (comparative more undue, superlative most undue)

1. Excessive; going beyond that what is natural or sufficient.

   To individuals who despise killings in any form, death penalty is undue punishment.

   • 2016 January 17, "Wealthy cabals run America," Al Jazeera America (retrieved 18 January 2016):

     But even if they don’t announce themselves on the cover of the Times business section, groups of millionaires exercise undue influence on every aspect of American life every day.

2. That which ought not to be done; illegal; unjustified.
3. (of a payment etc) Not owing or payable.