What does going off of someone said

I'd guess it means you're saying something that relates to what someone else said. so you are telling other people what someone else told you. Just a guess:)

“going off” means

1. get really mad and tell someone lots of things

2. did something well

3. to make a valid point

dr. kings dream speech

explanation:

it was late in the day and hot, and after a long march and an afternoon of speeches about federal legislation, unemployment and racial and social justice, the rev. dr. martin luther king jr. finally stepped to the lectern, in front of the lincoln memorial, to address the crowd of 250,000 gathered on the national mall.