Synonym word of overestimation:

aggrandizement, amplification, baloney, boasting, caricature, coloring, crock, elaboration, embroidery, emphasis, enlargement, exaltation, excess, extravagance, fabrication, falsehood, fancy, fantasy, figure of speech, fish story, flight of fancy, hogwash, hyperbole, inflation, jazz, line, magnification, misjudgment, misrepresentation, overemphasis, overestimation, pretension, pretentiousness, rant, romance, stretch, tall story, untruth, whopper, yarn