a. 1. Not due; not yet owing; as, an undue debt, note, or bond. [ 1913 Webster ]
2. Not right; not lawful or legal; improper; as, an undue proceeding. Bacon. [ 1913 Webster ]
3. Not agreeable to a rule or standard, or to duty; disproportioned; excessive; immoderate; inordinate; as, an undue attachment to forms; an undue rigor in the execution of law. [ 1913 Webster ]
Undue influence (Law), any improper or wrongful constraint, machination, or urgency of persuasion, by which one's will is overcome and he is induced to do or forbear an act which he would not do, or would do, if left to act freely. Abbott. [ 1913 Webster ]