under

preposition:in a lower place or position than; below
- The cat slept under the table.
preposition:at a lower level, layer, or grade than
- She has three people under her in the company hierarchy.
preposition:less than (a specified amount, age, or price)
- Children under 12 get in for free.
preposition:according to the rules or authority of
- The project was completed under the new manager's direction.
preposition:in a state of being subjected to a particular condition or process
- The bridge is under construction.
adverb:in or into a state of unconsciousness
- The anesthetic put the patient under for the surgery.