| 1. Off hand | (without preparation or delay) I am very poor in English grammar & can’t answer all the questions off hand. |
| 2. Over head and ears | (excessively) Mohan is over head and ears in love with Neena. |
| 3. Out of question | (certain) His success is out of question because he is working hard these days. |
| 4. Out of the question | (unlikely, uncertain) His success is out of the question because he is not working hard these days. |
| 5. Out of the woods | (out of danger) The patient is not out of the woods yet |
| 6. Order of the day | (in fashion) It is difficult to get any work done without bribery because bribery is the order of the day. |
| 7. On the score of | (on the grounds of) He was debarred from appearing in the examination on the score of indiscipline. |
| 8. On that score | (for the reason) You need not worry on that score. |
| 9. Over and above | (moreover, besides) I shall lend you books over and above what I have promised to give you in cash. |
| 10. Out and out | (completely) Shri Bhagat Singh was a patriot out and out. |
| 11. Off and on | [occasionally (now & then)] Since she is over busy these days, she visits me off and on. |
| 12. One’s Achilles heel | (a weak point) Howsoever powerful a person may be, he is vulnerable because of his Achilles’ heel. |
| 13. Off colour | (not in usual form ) Once a glamorous actress, she is off colour these days. |
| 14. Odds and ends | (scattered things) The thief made away with the odds and ends lying about the drawing room. |
| 15. Off the hook | (out of trouble) He is not yet off the hook because Income Tax department is making a thorough inquiry into his financial status. |
| 16. Oily tongue | (flattering words) He has often won over the enemies by his oily tongue. |
| 17. On the horns of dilemma | (in a fix) He is on the horns of dilemma in the matter of his marriage. |
| 18. One’s cup of tea | (to one’s liking) Teaching is not my cup of tea. |
| 19. Out of sorts | (to be unwell) Sohan had been out of sorts the whole day and could not do his office work properly. |
| 20. On its last legs | (about to collapse) In many sections of Indian society the system of child marriage is on its last legs. |
| 21. On the carpet | (to be under consideration) What is on the carpet these days is in the newspapers. |