Steal Your Thunder; Specious; Limelight;

Here's an origin that sounds specious to me. By the way, specious means superficially plausible, but actually wrong.  - which itself has a specious origin in late Middle English (in the sense ‘beautiful’) from the earlier Latin specious (fair).

I found that “steal your thunder” - which today means to take the attention or limelight away from someone. By the way, the term "limelight" comes from the discovery in the 1820s that heating calcium oxide with oxygen and hydrogen produces a brilliant white light. The light was used as a theatrical spotlight and to illuminate stages. 

Back to "steal your thunder" which is said to have a quite literal origin. In the 18th-century, playwright John Dennis wanted an authentic sound of thunder for his play. He invented a thunder-making machine, but his play flopped. Later, he learned that someone had seen his machine in action and made a similar one for another play. It was pretty much the same machine but was not credited with the invention. This other person had literally stolen his thunder.