under

/ˈʌndər/ preposition

Definition

BELOW › below something: She pushed her bag under the table. The children were sitting under a tree.

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. We don't serve alcohol to anyone under 18.

CONTROLLED BY › controlled or governed by a particular person, organization, etc: a country under military rule The restaurant is under new management. I'm managing the project and have three people under me.

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. Students are allowed to miss school under certain circumstances.

IN PROGRESS › used to say that something is happening at the moment but is not finished: A new 16-screen cinema is under construction. Several different plans are under discussion.

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'.

(Definition of under preposition from the Cambridge Learner's Dictionary © Cambridge University Press)