A political way of saying that someone disagrees with something they say.
I beg to differ about Mr Johnson's final assertion.
by BlackPohatu October 26, 2016
Definition: I beg to differ is a word used by dimwits who think they always know what's going on.
Example:

Joe: Hey I don't think that's true
Jane: I beg to differ
Joe: No like it's literally on their website saying it isn't true.
by JackXL February 9, 2021