The Collaborative International Dictionary of English v.0.48:
Soldering \Sol"der*ing\, a. & n. from Solder, v. t. [1913 Webster] Soldering iron, Soldering tool, an instrument for soldering, consisting of a bit or bolt of copper having a pointed or wedge-shaped end, and furnished with a handle. [1913 Webster]WordNet (r) 3.0 (2006):
soldering iron n 1: a hand tool with a heatable tip; used to melt and apply solder