Glossary

Controlled forest fire
"It is that which has been isolated and its advance and spread has been stopped within control lines." (RD 893/2013 of 15 November)
Fire danger
"Possibility of a forest fire occurring in a given place and at a given time". (RD 893/2013 of 15 November).
Forest fire
"Fire that spreads uncontrolled over forest fuels located in the forest. For the purposes of this guideline, fires occurring in areas adjacent to the forest or in transition with other urban or agricultural areas will also be considered as such." (RD 893/2013 of 15 November).
Forest fire extinguished
"Situation in which there are no longer any igniting materials on or within the perimeter of the fire and no further reproduction of the fire is possible". (RD 893/2013 of 15 November).
Forest-urban interface
"Area where buildings come into contact with the forest. The fire developed in this area, not only can reach the buildings, but can also spread inside the built-up areas, whatever the cause of origin". (RD 893/2013, of 15 November)
Hazard indices
"Indicative values of the danger of forest fire in a given area". (RD 893/2013 of 15 November).
Meteorological Information System for forest fire hazard estimation
"It is the set of actions and activities carried out by the State Meteorological Agency to provide meteorological danger indexes for the fight against forest fires and other complementary information, as well as the procedures for their transmission at national level and to the Autonomous Communities, especially in emergency situations." (RD 893/2013, of 15 November).
Mobilisation
"Set of operations or tasks for the implementation of means, resources and services for the fight against forest fires". (RD 893/2013, of 15 November).
Potential severity index of a forest fire
"Indicator of the damage that a forest fire is expected to cause, given the conditions in which it develops." (RD 893/2013, of 15 November).
Stabilized forest fire
"It is that which has been isolated and its advance and spread has been stopped within control lines". (RD 893/2013 of 15 November).
Vulnerability
"Degree of loss or damage that may be suffered by the population, property and the environment in the event of a forest fire". (RD 893/2013 of 15 November).
References:

The definitions have been extracted and translated of:

España. Real Decreto 893/2013, de 15 de noviembre, por el que se aprueba la Directriz básica de planificación de protección civil de emergencia por incendios forestales. Boletín Oficial del Estado, 7 de diciembre de 2013, núm. 293, pp. 97616 a 97638.