above - below

1. at a higher or lower elevation than another thing.

• The Global Positioning System is a network of 24 satellites 12,000 miles above the earth.
• That city is only 250 feet above sea level.
• The Netherlands are below sea level.
• I looked up and saw some birds flying above me.
• She held a lamp above her head.
• When the thief saw the police, he raised his hands above his head.
• Her portrait hung above his fireplace.
• Mary lives on the floor above me, but John lives on the floor below.
• The towers of the old castle rose above the trees.
• He had a tattoo above his right wrist.
• Standing on top of the mountain, he could see the village below.

2. in a higher or lower position of authority than another person

• A major is above a captain.
• A sergeant is below a captain.

3. higher or lower in amount or degree

• Our operating costs are way above normal.
• The students' SAT scores were well above average this year.
• Last year their SAT scores were below average.
• In order to be admitted to graduate school, students must have a GPA (grade point average) of 3.0 or above.
• His approval rating is above 60%.
• His approval rating has fallen below 70% for the first time since January.
• Unemployment was above 6% in 1994.

4. higher or lower than zero when speaking of temperatures (the word zero is often omitted)

• The record temperature for our state is 48 degrees below zero.
• It was only 25 above today. (25 degrees above zero)
• It was ten below last night. (10 degrees below zero)

5. above all means more than anything else

• Americans value freedom above all.
• He was, above all else, a gentleman.

6. mentioned earlier or later in a piece of writing

• For an explanation, see below.
• The report mentioned above was published in 1987.
• Mr. Joshua Samuels, pictured above, founded the company in 1888. (His picture appears earlier in the text or toward the top of the page.)
• 
  Above is also used as a noun in this sense:
  
  
• None of the above (an option on a multiple-choice test indicating that none of the preceding answers is correct)
• Students are required to write a report on one of the above. (instructions on a teacher's reading list indicating one of the books previously mentioned)

7. above is used is some special senses:

a. not subject to

• He is above suspicion. (People do not consider him capable of doing something wrong.)

b. too good or noble to do something bad

• He is above such tactics. (His character is too good to permit him to do such things.)

c. not too proud to do something (used with not)

• He is not above asking for help.

d. in preference to

• My boss favors certain employees above others.

8. above and beyond is an idiomatic expression which means in addition to, or more than normal

• I will have to spend $5,000 above and beyond the $12,000 I have already spent to finish remodeling the house.

• The soldier's actions went above and beyond the call of duty. (He did something that was more heroic than what was expected of him.)

over - under

1. Above and below indicate only a higher or lower position, while over and under usually indicate higher or lower in a straight line. Look at the diagram.

A, B, and C are above X.

B is over X.

• I could see the flag flying over the embassy.

2. Above and below indicate a higher or lower position of authority in general, whereas over and under indicate immediate authority (that the person has the power to order the other person).

For example, a major is above a captain, but a major in the U.S. army is not over a captain in the Canadian army. American officers are over/under American soldiers, and Canadian officers are over/under Canadian soldiers.

3. over is used to mean more than

• He has worked there over five years.
• The government has spent over $20 million on the project.
• I spent over 20 hours working on the report.

4. over is commonly used to mean during

• Our profits have declined 37% over the last three years.
• DVD sales are expected to increase dramatically over the next few years.
• He said there were many efforts to discredit him over the years.
• How many hours will you spend sleeping over the rest of your lifetime?
• Fred prepared for his test over the weekend.
• What did you do over your vacation?
• Jobs in software have fallen by almost 2% over the past year.

5. over is used to mean while having a meal or a drink

• He told me his plans over lunch.
• We reviewed the contract over coffee.
• Let's talk about it over a drink.

6. over is used to mean spanning, crossing, or moving across

• A bridge had to be built over the raging river.
• The city installed a walkway over the busy street.
• The planes flew over the city.
• "Moon Over Miami"

7. over is used for crossing land, mountains, etc.

• The traveled over rough terrain for three days before coming to flat land.
• They decided it was easier to go around the mountains rather than over them.

8. over or all over can mean in many different areas

• Nowadays people all over the world use the Internet.
• Record high temperatures were recorded over most of the southwest yesterday.

9. over is used to mean on (a person or thing)

• She wore a veil over her face.
• She put her hands over her ears.
• They poured cold water over his face.
• As it was raining, he put his coat over his head.
• I spilled tea all over my new pants.

10. Just as over can mean more than, under can mean less than.

• You cannot buy alcohol in California if you are under 21.
• That car looks expensive, but it is under $18,000.
• That CEO owns just under 12% of the company stock.

11.over and above means in addition to

• Congress authorized $10 billion over and above the $45 billion already requested.

12.over and over means again and again, many times, repeatedly

• People try over and over to lose weight.
• Our local TV station has shown the same movie over and over.

13. under can mean below the surface of something

• How long can you swim under the water without coming up for air?
• He had a splinter under his skin.

14. under is often used in the sense of according to the provisions of (an agreement, law, etc.)

• Under the terms of the merger, the stock in ABC company will be redeemed at 2 to 1.
• Under California law, one must be 21 or over to buy alcoholic beverages.

15. under can mean in a category or heading, or using a name

• Please file those invoices under "Accounts Receivable."
• I think the book you are looking for is listed under "Finance."
• Mrs. Thompson is still listed in the phone book under her maiden name.
• He registered under a false name.

16. under can mean affected by

• He was arrested because he was under the influence of drugs.
• He received a ticket for driving under the influence of alcohol.
• She has been sick several times this term because she is under a lot of stress.