Synonyms: courage, bravery, nerve, guts
courage: the ability to deal with a dangerous or unpleasant situation
Example: She showed great courage in attacking the burglar. I didn’t have the
courage to disagree with him.
bravery: the ability to do dangerous or unpleasant things without being afraid
Example: We admired her bravery in coping with the illness. He won an award for bravery.
nerve: the ability to keep your fear under control in order to achieve something
Example: It takes a lot of nerve to disagree with your friends. He went over to speak to her but at the last minute he lost his nerve.
guts: (informal) courage
Example: She had the guts to tell the boss he was wrong.
cowardice: the state of being afraid and not brave