From Longman Dictionary of Contemporary Englishsoldering ironˈsoldering ˌiron noun [countable] 
TZTIa tool which is heated, usually by electricity, and used for melting solder and putting it on surfaces
TZTIa tool which is heated, usually by electricity, and used for melting solder and putting it on surfacesExamples from the Corpus
soldering iron• The reflection of a soldering iron in protective goggles as the musical weapons are forged.• Like the tip of a soldering iron.• The only solution for this is to use a soldering iron to lengthen them!• In general, designers no longer work with a heap of transistors and a hot soldering iron. 