To exaggerate, overemphasize, overstate. An idiom. The 'over' is added unnecessarily and its usage is virtually always synonymous with a mere 'exaggerate', rather than a different word, as 'exaggerate' is not a neutral usage verb like the word 'do'. There is no threshold for the word 'exaggerate', so it is not possible to overdo. To 'overexaggerate' is to 'overoverstate'.
Only idiots say overexaggerate.
by adsmo November 26, 2010