fantastic

adjective

1 it's a fantastic notion, but it would explain everything:

fanciful, extravagant, extraordinary, irrational, wild, mad, absurd, far-fetched, nonsensical, incredible, unbelievable, unthinkable, implausible, improbable, unlikely, doubtful, dubious;

strange, peculiar, odd, weird, eccentric, insane, whimsical, capricious;

imaginary, visionary, romantic, unreal, illusory, make-believe;

informal crazy, cock-eyed, oddball, off the wall;

British, informal barmy, potty, daft.

▷antonyms rational.

2 a memory of fantastic accuracy:

tremendous, remarkable, great, terrific, enormous, huge, striking, impressive, outstanding, phenomenal, monumental, overwhelming.

3 the mountains assumed weird and fantastic shapes:

strange, weird, bizarre, outlandish, queer, peculiar, eccentric, grotesque, freakish, surreal, exotic;

whimsical, fanciful, quaint, imaginative, elaborate, ornate, intricate, rococo, baroque, phantasmagoric, Kafkaesque.

▷antonyms ordinary, unremarkable.

4 informal a fantastic new car:

marvelous, wonderful, sensational, magnificent, outstanding, superb, superlative, excellent, very good, first-rate, first-class, dazzling, out of this world, breathtaking;

informal great, terrific, tremendous, fabulous, fab, mega, super, stellar, ace, magic, A1, cracking, cool, wicked, awesome, amazeballs, way-out, def, supercalifragilisticexpialidocious;

British, informal brilliant, brill, smashing, bosting;

Australian, New Zealand, informal bonzer;

British, informal , dated spiffing, topping, tip-top, top-notch, capital.

▷antonyms ordinary, poor.