Debbie downer

[Rihanna]

Etymology: From the Saturday Night Live character Debbie Downer, played by Rachel Dratch
Function: Noun

a: a person who says something terribly depressing (a [downer]), typically only tangentially related to the present circumstance or topic of conversation, and thereby destroys the positive atmosphere. b: a statement that is charactaristic of Debbie Downer

Usage note: In the skit, following each downer Debbie voices, a trombone plays a wah waaah ([sad trombone]) sound effect and the camera zooms in on Debbie Downers face, which is twisted in comic despair.

[Little_Girl]

A person with an incessant need to bring down the collective mood and general ambience of a group-chill, synonomous with Larissa.

[Rihanna]

Someone who throws in a negative comment or brings down the mood when something positive happens or is said.

[Mark Zuckerberg]

A Facebooker who uses Facebook as a media to convey sad, woeful, and depressing stausi for no reason, bringing the morale of all that see plummeting to the ground.

[Donald Trump]

(noun) a pessimist, one who looks on the downside of things, has zero confidence in themselves, criticizes themselves, sees the glass as half empty, you get the picture.
kind of like Grace Dimond

[Mark Zuckerberg]

The person who, in which a state of high, decides to down on a chill-group discussion.

[Tina]

A girl who always brings up something negative about herself,co worker,life or in the news. Everything that comes out of her mouth is negative.