The term BUNSEN is associated with three crossword solutions: BURNER (6 letters), ETNAS (5 letters), and LAB (3 letters). The first solution, BURNER, refers to the Bunsen BURNER, an instrument used in laboratories to produce a single open gas flame. It was invented by Robert Bunsen in the mid-19th century and is still widely used today. The second solution, ETNAS, is a reference to Mount Etna, an active volcano located on the island of Sicily. Robert Bunsen conducted experiments on the volcano in the 1850s, which helped to further his research into geology and chemistry. The third solution, LAB, is a shortened form of laboratory, where the Bunsen BURNER is used.