Well, I'm doing a course on writing at work and today there was a competition to invent a new word. Mine is meganym.
Meganym - overly positive (or negative) superlative used in place of a more appropriate synonym.
Examples: 'terrible' instead of 'bad'; 'superb' instead of 'good'.
Used in an ironic sentence: 'the overuse of meganyms in contemporary speech exasperates me'.
Feel free to use it :)