unlead
Unlead is a term that can refer to several different concepts, depending on the context. In the realm of combustion engines, "unlead" is a colloquial term for unleaded gasoline. Unleaded gasoline is a type of fuel for internal combustion engines that does not contain added lead compounds. The phasing out of leaded gasoline began in the 1970s due to environmental and health concerns associated with lead pollution. Today, most gasoline sold worldwide is unleaded.
Beyond fuel, "unlead" can also describe the act of removing a lead or lead-like substance from something.
In a more metaphorical sense, "unlead" could imply the removal of a burden, restriction, or negative influence.