realm
UK: relm | US: relm
n. a kingdom or domain, especially one governed by a monarch
n. a field or sphere of activity, interest, or knowledge
The word "realm" originates from Old French realme (modern royaume), derived from Latin regalis (royal). The morpheme real preserves the Latin root reg- (king), while -m evolved as a shortened form of the suffix -dom (as in "kingdom"), denoting a state or territory. Over time, "realm" expanded beyond literal kingdoms to metaphorical domains (e.g., "realm of science").
The king's realm extended across vast lands.
She is a leading expert in the realm of artificial intelligence.
The novel transports readers to a magical realm.
Discussions about ethics fall within the realm of philosophy.
His influence spans the realm of politics and business.