English
firehole
From fire + hole.
Proto-Indo-European *péh₂wr̥
…
Proto-Germanic *fuïr
Proto-West Germanic *fuir
Old English fȳr ‘fire’
Middle English fyr
English fire
Proto-Germanic *hulaz ‘hollow’
Proto-Germanic *hulą ‘hollow space’
Proto-West Germanic *hol ‘hollow space, cavity’
Old English hol ‘hole, hollow place’
Middle English hole
English hole
Today it means
noun An opening fitted with a door, giving access to the firebox of a steam locomotive, through which coal can be shovelled and the fire tended.
Language periods are conventional ranges, not dates for this word.
Etymograph / firehole