Not paying attention to or failing to notice something.

अनदेखी करने वाला

English Usage: She was often nonobservant of the changes in her surroundings.

Hindi Usage: वह अक्सर अपने आस-पास के परिवर्तनों की अनदेखी करने वाली थी।

The act of failing to observe or notice something.

अनुपयुक्तता

English Usage: His nonobservance of the rules led to his disqualification from the contest.

Hindi Usage: उसके नियमों की अनुपयुक्तता ने उसे प्रतियोगिता से अयोग्य घोषित कर दिया।