adverb

 

below the surface below the surface of something

The child was swimming and suddenly started to go under.

 

less than less than a particular number, amount, or age

I want a computer that is £2000 or under.

 

preposition

 

below below something

She pushed her bag under the table.

 

below the surface below the surface of something

He could only keep his head under the water for a few seconds.

 

less than less than a number, amount, or age

You can buy the whole system for just under $2000.

 

controlled by controlled or governed by a particular person, organization, etc

a country under military rule

 

rule/law according to a rule, law, etc

Under the new law, all new buildings must be approved by the local government.

 

in a particular state in a particular state or condition

The President is under pressure to resign.

 

in progress used to say that something is happening at the moment but is not finished

A new 16-screen cinema is under construction.

 

name using a particular name, especially one that is not your usual name

He also wrote several detective novels under the name, Edgar Sandys.

 

place in list used to say which part of a list, book, library, etc you should look in to find something

Books about health problems are under 'Medicine'.