IPA: //sʌlˈfjʊəriəs//
KK: /sʌlˈfjʊrəs/
Relating to or containing sulfur, often having a strong smell like that of rotten eggs.
The sulphureous fumes from the volcano could be smelled from miles away.
Sulphureous is derived from "sulphur" (from Latin "sulphur", meaning brimstone or sulfur) and the suffix "-eous" (meaning possessing the qualities of). The word sulphureous refers to something that has the qualities or characteristics of sulfur, often associated with a strong, pungent smell.
Think of 'sulphur' as the source of a strong smell, and remember that 'sulphureous' describes something that has the qualities of sulfur.