Definition of "underfired"
underfired1
adjective
not generally comparable, comparative more underfired, superlative most underfired
(comparable, ceramics) Fired at a low (or excessively low) temperature.
Quotations
[W]hen the enamel is thick and a little underfired it will be lighter in color and have a pitted surface. Going further, extremely thick areas that are well underfired will be blistered, cracked, or bubbly.
1997, Roger A. Wallace, Joseph A. Melaro, “Impact of Physical Characteristics of Water Heater Enamels on Water Resistance”, in Proceedings of the 59th Porcelain Enamel Institute Technical Forum […] (Ceramic Engineering and Science Proceedings; vol. 18, no. 5), Westerville, Oh.: Published for the Porcelain Enamel Institute by the American Ceramic Society, pages 160–161
In terms of its body composition, Ru ware is essentially a slightly underfired (1200°–1250°C) stoneware with a high-alumina, low-iron clay of typical north Chinese composition.
1999, Nigel Wood, “The Stonewares of North China”, in Chinese Glazes: Their Origins, Chemistry, and Recreation, London: A & C Black; Philadelphia, Pa.: University of Pennsylvania Press, page 127, column 1
An underfired or short-fired piece is likely to break if you attempt to change its shape because it is built of many small particles of silver, joined together at the edges. A properly made, fully sintered and fully annealed metal clay piece should be able to stand up to any traditional metalsmithing technique.
2010, Kate McKinnon, Sculptural Metal Clay Jewelry: Techniques and Explorations, Loveland, Colo.: Interweave Press, page 27
Some old, underfired clay pantiles might be damaged by button mosses rooting in cracks and fissures. But most post-war tiles are hard enough to withstand a bit of moss growth.
2014 October 26, Jeff Howell, “Is the Japanese knotweed threat exaggerated? Our troubleshooter calls for calm about Japanese knotweed in the garden – and moss on the roof ”, in The Daily Telegraph (Property), London: Telegraph Media Group, archived from the original on 12 February 2015
(not comparable, cooking) Of a cooker: having a heat source that is underneath the food being cooked.
Quotations
Steak lovers want a charred surface and a rare, even cold, center. A high-tech overfired broiler is the secret. This kind of broiler delivers tremendous heat that is both predictable and consistent. Some establishments use the underfired version, which has the advantage of searing the bits of dripping fat, which gives the meat a barbequed taste. [...] The disadvantage of the underfired grill is the potential for flareups, which can cause a burned spot or carbonization. Not only do these taste bad, but they are also carcinogenic. Home grills are underfired; they must be watched carefully.
2009, Peter Osbaldeston, “Steakhouses”, in The Palm Springs Diner’s Bible: A Restaurant Guide […], Gretna, La.: Pelican Publishing Company, page 250
Under-fired (under-heated) grills. The heat source for these is underneath the grill. Under-fired grills are used to cook food quickly, so they need to reach a high temperature. This type of grill makes criss-cross marks on the food, known as quadrillage.
2014, Keyth Richardson et al., chapter 7, in Basic Cookery for Foundation Learning, London: Hodder Education