Main entry: sudden
Definition: happening without warning or in a short space of time
Usage: a sudden storm; a sudden decision; a sudden cure
Antonyms: gradual
Definition: proceeding in small stages
Antonyms: nonexplosive
Definition: not explosive
Antonyms: dull
Definition: not having a sharp edge or point
Antonyms: dull
Definition: not keenly felt
Antonyms: natural
Definition: (of a musical note) being neither raised nor lowered by one chromatic semitone
Antonyms: flat
Definition: (of a musical note) lowered in pitch by one chromatic semitone