slipup (?.)

• balk
• bevue
• blooper
• blunder
• boner
• bungle
• error
• false move
• false step
• fluff
• inadvertence
• inadvertency
• lapse
• lapsus calami
• lapsus linguae
• loose thread
• miscue
• miss
• misstep
• mistake
• near-miss
• omission
• oversight
• slip
• stumble
• trip
• wrong step