Bob_McMillan said:
I love The Flash, even though it's pretty much a more colorful carbon copy of Arrow. One thing I don't get though is how "metahuman" is an insult. When Plastique was told she was a meta, she looked angry and Caitlin had to tell her it was just an expression. In the Arrow/Flash crossover, Oliver told Barry not to call the metas metahumans in a disapproving tone. I think there are a few more instances but I cant remember them.
In the conversation between Barry and Oliver, I believe Oliver's point was that Barry was not taking things serious enough, as if it was all a game or a "comic book" to him. Oliver's world involves a darker, more lethal, side of humanity, which they touched on in the crossover.
I may be wrong but I gather Plastique's reaction was more of a "what did you just call me?" reaction as the term metahuman has not been widely used outside the Flash's clique up to that point.
Seishisha said:
As far as i can remember metahuman is the basic term to describe anyone in the DC universe who has the metagene, i believe the term also has some crossover with characters like superman who despite being alien has simular traits to a typical metahuman.
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Side note all DC metahumans gain their power from the sun just like superman.
Not necessarily. Depending on if you are looking at The Flash/ The Arrow TV Continuity or the DC Comics. In the shows, so far all meta's are the product of the Star Labs experiment event. In the comics, a metahuman is someone that has internal powers, as opposed to getting them from an outside source. These are situations where the metagene gets activated by some event.
Generally the source of someone's powers can be broken down into a handful of categories:
Metahumans: humans like the Flash, or Killer Croc, that have internal powers above the normal human. Also sometimes used to describe "human-like" aliens with internal powers like Superman, although I believe that is used incorrectly.
Magic: Wonder Woman, Captain Marvel/ Shazam, John Constantine. Someone that gets their powers from a mystical source.
Skill or Technology: Batman, Lex Luthor, Green Arrow. Normal humans that get their abilities from training, skill, or technological gadgets they use.
As far was where people gain their powers, I am a few episodes behind on The Flash tv series so I do not know if they have changed this yet, but in the comics, the Flash taps into an extra-dimensional energy called the Speed Force for his powersource, not the sun. Other metas also have different sources for their powers other than the sun.