A moment in time (or all the time for Richard) where something stupid/retarded happens. Usually during times of Richard Moments, the "Richard" is completely useless. Never let a person who has "Richard Moments" to do something for you. You are better off doing it yourself. "Richard Moment" is the putting it nicely whereas the real term is "Retard Moment"
Me: Go get my keys.
Richard: Uhhhmm? Durrrrhhh?
Me: Are you having a Richard Moment again? Damn these Richard Moments.