The adj fantastic has 7 senses (first 4 from tagged texts)
1. (4) antic, fantastic, fantastical, grotesque -- (ludicrously odd; "Hamlet's assumed antic disposition"; "fantastic Halloween costumes"; "a grotesque reflection in the mirror")
2. (3) fantastic, grand, howling, marvelous, marvellous, rattling, terrific, tremendous, wonderful, wondrous -- (extraordinarily good; used especially as intensifiers; "a fantastic trip to the Orient"; "the film was fantastic!"; "a howling success"; "a marvelous collection of rare books"; "had a rattling conversation about politics"; "a tremendous achievement")
3. (2) fantastic, wild -- (extravagantly fanciful and unrealistic; foolish; "a fantastic idea of his own importance")
4. (1) fantastic, fantastical -- (existing in fancy only; "fantastic figures with bulbous heads the circumference of a bushel"- Nathaniel Hawthorne)
5. ace, A-one, crack, fantastic, first-rate, super, tiptop, topnotch, tops -- (of the highest quality; "an ace reporter"; "a crack shot"; "a first-rate golfer"; "a super party"; "played top-notch tennis"; "an athlete in tiptop condition"; "she is absolutely tops")
7. fantastic, phenomenal -- (exceedingly or unbelievably great; "the bomb did fantastic damage"; "Samson is supposed to have had fantastic strength"; "phenomenaRl feats of memory")