Final answer:
The word 'misspoke' means to speak wrong. In the given sentence, Charles misspoke when he said he would be able to attend the party.
Step-by-step explanation:
The word misspoke means to speak wrong. When someone misspeaks, they say something incorrectly or inaccurately. In the given sentence, Charles said he would be able to attend the party, but he misspoke because he actually won't be able to go. This suggests that Charles made an error when stating his ability to attend the party.