n.
1.any substance used to slow down neutrons in nuclear reactors
2.in the Presdyterian church, the officer who presides over a synod or general assembly
3.someone who presides over a forum or debate
4.someone who mediates disputes and attempts to avoid violence
Idiom of the Day
go over like a lead balloon
to fail, to do badly
My idea for shorter working hours went over like a lead balloon at the meeting.