When it comes to describing a "bright idea," there are a plethora of synonyms available to use. Some options include "brilliant concept," "innovative proposition," "genius notion," "clever scheme," and "smart plan." Other possibilities include "creative solution," "ingenious concept," "astute idea," "intelligent proposal," and "wise thought." These synonyms all convey a similar meaning to a "bright idea" and can be used interchangeably depending on the context and tone of the piece of writing or conversation. Regardless of which synonym is chosen, all of these words can help to highlight the value and importance of a particularly impressive idea.