THESE DON'T MEAN ANYTHING ANYMORE THANKS TO OVERUSE

The following phrases and expressions have been rendered completely useless, thanks to us using them in more and more generous ways until their meaning becomes so vague that we might as well not use them at all anymore.

Jumping the Shark : originally a direct reference to a particular scene in a particular popular TV series.
Intended meaning : is supposed to designate a crucial, irreversible moment in a story or person's career where they lose all credibility. The crucial part is that the blunder commited is supposed to be so major that no recovery is possible. For example, the death of a very important (non superhero) character in a series; or a politician being convicted of a major crime and going to jail.
Current meaning : whenever anybody does anything we don't like. "Lucas really jumped the shark with the Ewoks"; "My friend totally jumped the shark with that Facebook post".

Dunning-Krueger : the Dunning-Krueger Effect is a cognitive bias in which low-ability individuals suffer from illusory superiority, mistakenly assessing their ability as much higher than it really is. It was originally discovered with a rather specific set of studies in which people of different abilitty levels were systematically unable to evaluate in which percentile they were located regarding their own performance.
Intended meaning : it's only meaningful to talk about DKE when you're talking about groups of people, and you have some objective way of measuring the relative performances of the members of that group.
Current meaning : used to describe anyone you think is not as good as he thinks; basically a synonym of "bragger" or blowhard".

Click-Bait : a type of internet article written with the overt intent of generating "clicks", or page views.
Intended meaning : "click-bait" articles are supposed to be mostly devoid of any content at all, political or otherwise, take very little time to write, and most importantly be spread over several pages in order to maximize clicking and ad revenue. You can have a Top-50 of something spread out over 50 pages with a single sentence and a lone picture on each page as an egregious example.
Current meaning : an article that says something you don't feel like hearing, no matter how true, rational or articulate it is. "CNN is just click-bait"; "Fox News is just click-bait".

Racist/Sexist/Misogynist/Homophobe/Transphobe/Fascist/White Supremacist : you can look up the official definitions in a dictionary I guess.
Current meaning : words you call someone if you have nothing intelligent to say about or against them or their arguments.