(1) (n) something depressing. Ex. "That's a bring down". (2) (v) Ex. "That brings me down".

move something or somebody to a lower position; "take down the vase from the shelf"

impose something unpleasant; "The principal visited his rage on the students"

cause to be enthusiastic; "Her playing brought down the house"

cut down on; make a reduction in; "reduce your daily fat intake"; "The employer wants to cut back health benefits"

to depress; as a noun, bringdown, one who depresses.

Something or someone that ruins your day, and makes you lose your high. "My ol' man's bringin' me down."