extraordinarily good or great
used especially as intensifiers
e.g. a fantastic trip to the Orient
e.g. the film was fantastic!
e.g. a howling success
e.g. a marvelous collection of rare books
e.g. had a rattling conversation about politics
e.g. a tremendous achievement
Synonym: fantastic grand howling(a) marvelous marvellous rattling(a) terrific tremendous wonderful