O

18 only --adj. being the single one or ones; no more than (“We have only two dollars.”)

23 opposite --adj. different as possible; completely different from; exactly the other way (“North is the opposite direction from south.”)

31 other --adj. different; of another kind; the remaining one or ones of two or more (“That man is short; the other is tall.”)

15 old --adj. not young or new; having lived or existed for many years

32 our --adj. of or belonging to us

34 out --adv. away from the inside; opposite of in

7 off --adv. away; at a distance; condition when something is no longer operating or continuing; not on; not connected

13 often --adv. many times

17 once --adv. one time only

35 over – -conj. above; covering; across, in or on every part of (“all over the world”)

25 or – -conj. giving another of two choices; giving the last of several choices

21 opinion -n. a belief based on one’s own ideas and thinking

29 organism -n. a living thing, often so small it can be seen only through a microscope

8 offensive -n. a military campaign of attack; -adj. having to do with attacking

28 organ -n. a part of the body that has a special purpose, such as the heart or brain

11 officer -n. a person in the military who commands others; any person who is a member of a police force

12 official -n. a person with power in an organization; a representative of an organization or government; -adj. of or about an office; approved by the government or someone in power

10 office -n. a room or building where business or work is done; a public position to which one is elected or appointed

14 oil -n. a thick liquid that does not mix with water and that burns easily; a black liquid taken from the ground and used as fuel

5 ocean -n. the area of salt water that covers almost seventy–five percent of the earth’s surface; any of the five main divisions of this water

16 on -prep. above and held up by; touching the upper surface of (“The book is on the table.”); supported by (“He is on his feet.”); about (“The report on the meeting is ready.”); at the time of (“He left on Wednesday.”)

6 of -prep. made from; belonging to; about; connected to; included among

1 obey -v. to act as one is ordered to act

22 oppose -v. to be against; to fight against

20 operate -v. to do work or a job; to cut into the body for medical reasons

33 oust -v. to force to leave; to remove by force

27 order -v. to give a command; to tell someone what to do;-n.a command; the correct or normal way things are organized; a peaceful situation in which people obey laws

38 own -v. to have or possess for oneself

24 oppress -v. to make others suffer; to control by the use of unjust and cruel force or power

37 owe -v. to pay or have to repay (usually money) in return for something received

9 offer -v. to present or propose;-n.the act of presenting or proposing; that which is presented or proposed

30 organize -v. to put in order; to put together into a system

36 overthrow -v. to remove from power; to defeat or end by force

2 object -v. to show that one does not like or approve; to protest;-n.something not alive that can be seen or touched

19 open -v. to start (“They opened talks.”); -adj. not closed; not secret

4 occupy -v. to take and hold or to control by force

26 orbit -v. to travel in space around a planet or other object;n. the path or way an object travels in space around another object or planet

3 observe -v. to watch; to look at carefully; to celebrate orhonor something (“They will observe the anniversary of the day she was born.”)

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S   T  U  V  W.  X - Y - Z