an adjective used when "fucking sweet" just doesn't cover it. Usually pertaining to sexual encounters with hot women but can also be used to fucking agree strongly, or exclaim in fucking rejoice.
Means the exact opposite of wonderful. Seeing as how fuck has become a fad to say when something bad happens, if you combine the two its like saying fuck x10
"Dude i totally spaced and forgot to go to work. Wonderfuk."
"I forgot to feed my moms favorite bird, now im wonderfuked"