Geol. [a. Sp. caldera = Pg. caldeira, F. chaudière cauldron, kettle, boiler:—L. caldāria, pl. of prec.] A deep cauldron-like cavity on the summit of an extinct volcano.
1865. Lyell, Elem. Geol. (ed. 6), 632. Enlarged afterwards into a caldera.
1875. Watts, Dict. Chem., VII. 553. [In] the valley of Furnas … the soil is now perforated by a number of geysers. The three largest and most active of these are called ‘caldeiras.’
