Adjective: Something just so great, something that makes you dumbstruck with utter "Ah"
Lucy is so fantastamazing for getting me that Taylor Swift autograph.
by underclasshero121 March 14, 2011
A compound word combining "fantastic" and "amazing." It is used when something is so wonderful that it can barely be fathomed.
Samrat's various karate achievements were so fantastamazing that words couldn't even describe it.
by lucybee March 14, 2011