chthonian /(k-)thōˈni-ən/ or chthonic /(k-)thonˈik/

1. Relating to the earth or the underworld and the deities inhabiting it
2. Ghostly

• fire engine
• fire engines
• fire escape
• fire escapes
• fire extinguisher
• fire extinguishers
• fire-eyed
• firefight
• firefighter
• firefighters
• firefighting
• firefights
• fire-flag
• fire-flags
• fire-flaught
• fireflies
• firefloat
• firefloats
• firefly
• fire-grate
• fire-grates
• fireguard
• fireguards
• fire-hook
• fire-hooks