what does "colored man 'mean?

It's a very old term for a black man. It's hard to explain in better detail without going into recent American history.

A "colored man" would be a man of the Negroid race, who has dark skin. His ancestors originally came from sub-Saharan Africa. In the United states, the word "colored" is not in modern use. The term African-American is the preferred designation.

A book written before the latter part of the 20th century, might very well refer to a "colored man".

express my thanks
I'm greatful to all of you ,especially Fri Jun 09.You have replied me more than one posts.You're ready to help others .Thank you very much .