unleaded

[uhn-led-id]

adjective

(of gasoline) containing no tetraethyllead; lead-free.
Printing. not separated or spaced with leads, as lines of type or printed matter.

noun

an unleaded product, especially gasoline that contains no tetraethyllead.

Origin of unleaded

First recorded in 1605–15; un-1 + lead2 + -ed3
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for unleaded

unleaded

adjective

(of petrol) containing a reduced amount of tetraethyl lead, in order to reduce environmental pollution
not covered or weighted with lead
printing (of lines of type, etc) not spaced or separated with leads; solid

noun

petrol containing a reduced amount of tetraethyl lead
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for unleaded
adj.

1610s, from un- (1) "not" + leaded (see lead (n.)). In reference to gasoline, from 1965.

Online Etymology Dictionary, © 2010 Douglas Harper