'Mark Antony shall say I am not well,
And, for thy humour, I will stay at home.'
What does this mean?

These words were spoken by Caesar because Calpurnia did not want him to go to the Senate as she had a bad dream. At first, Caesar did not listen to hear and insisted on going to the Senate but later with Calpurnia's begging, Caesar eventually decided not to go to the Senate and thus he said the lines.