To obviate (دور کرنا) a problem or need means to remove or prevent it, thereby making it 'unnecessary' (غیر ضروری بنا دینا).

Obsequious (چاپلوس) means obedient or attentive to an excessive degree. 'Excessively submissive' (حد سے زیادہ فرمانبردار) or servile is the definition.

Obscure (مبہم) means not discovered or known about; uncertain or 'hidden' (پوشیدہ). 'Hazy' (دھندلا) is also a good synonym, but 'hidden' captures the sense of being unknown. 'Intelligible' (قابل فہم) is the antonym.

Oblivious (بے خبر) means not aware of or concerned about what is happening. 'Forgetful' (بھولنے والا) or unaware is the best synonym. 'Observant' (تیز نظر) is the antonym.

Oblique (ترچھا) means not expressed or done in a direct way; 'indirect or evasive' (بالواسطہ یا مبہم). 'To the point' (براہ راست) is the antonym.

Obdurate (ضدی) means stubbornly refusing to change one's opinion or course of action. 'Stubborn' (ہٹ دھرم) is a direct synonym.

Notorious (بدنام) means famous for some bad quality or deed, thus having 'a bad reputation' (بری شہرت). 'Honor and acclaim' (عزت اور تعریف) is an antonym.

A notion (خیال) is a concept, belief, or vague 'impression' (تاثر) about something. 'Fact' (حقیقت) is an antonym, as a notion may not be true.

Notable (قابل ذکر) means 'worthy of notice' (قابل توجہ) or attention; remarkable.

A nostrum (جعلی دوا) is a 'quack medicine' (عطائی دوا) or a scheme of questionable effectiveness. 'External opening in the nose' (نتھنا) is a 'nostril'.