Main entry: suddenly, dead, short, abruptly
Definition: quickly and without warning
Usage: he stopped suddenly
Main entry: all of a sudden, suddenly, of a sudden
Definition: happening unexpectedly
Usage: suddenly she felt a sharp pain in her side
Main entry: on the spur of the moment, suddenly
Definition: on impulse; without premeditation
Usage: he decided to go to Chicago on the spur of the moment; he made up his mind suddenly