Synonyms of wackiest

1 Syllable
wild, daft, odd, mad, nuts
2 Syllables
crazed, silly, screwy, foolish, zany, loony, balmy, nutty, absurd, crazy
3 Syllables
erratic, insane, lunatic, demented, eccentric, deranged, hare-brained
4 Syllables
irrational, preposterous
5 Syllables
unpredictable