a soft heavy grey metal that melts easily and is poisonous, used to cover roofs, or in the past, for water pipes. It is a chemical element: symbol Pb
2 [uncountable and countable]D
the central part of a pencil that makes the marks when you write
if a suggestion or joke goes down like a lead balloon, people do not like it at all
4 [uncountable] American English old-fashioned
They filled him full of lead.
sheets of lead used for covering a roof
narrow pieces of lead used for holding small pieces of glass together to form a window