(idiomatic, often with 'on') To take harsh action (against), as when enforcing a law more stringently than before.

Used other than figuratively or idiomatically: see track, down. / (idiomatic) To hunt for or locate; to search for; to find.

(transitive) To make (something) lower (especially of clothes). / (transitive) To demolish or destroy (a building etc.). / (transitive) To cause to fall to the floor

Used other than figuratively or idiomatically: see cut, down. / (transitive) To bring down by cutting. / (idiomatic, transitive) To insult, to belittle. / (idiomatic) To reduce the amount of something.

(idiomatic) wasted or irretrievable.

(physics) A quark having a fractional electric charge of -1/3 and a mass of about 4 to 8 MeV. / Symbol: d

(physics) the antiparticle of a down quark

(computing) A dynamic menu; a list of options in a computer application which appears below a heading when it is selected, and remains only as long as the user needs it.

That can be pulled down (lowered).

(mathematics) Of a real number, converted to an integer by having its fractional component removed.