An unleaded fuel.
"He pumped a full tank of unleaded into his car before heading out for a long drive."
past tense of unlead
"After years of being led by a rigid manager, she finally unleashed her own creative vision on the team."
not having leads between the lines
"The old manuscript was difficult to read because the ink had faded, leaving the text unleaded and nearly illegible."
Without lead.
"He filled up his car at the station to make sure he was putting in unleaded gas without any harmful lead additives."