realm

The word “realm” means a kingdom or territory ruled by a monarch or supreme authority. In plain terms, a kingdom, or more loosely, a whole area or domain of something (like "the realm of possibility").

“Realm” is pronounced rehlm (/ɹɛlm/ in IPA).

Here is “realm” used in a sentence: “The knight swore loyalty to the king and his realm.”

Words with a similar meaning to “realm” include country, land and kingdom.

“Realm” is a noun.

The word “realm” dates back to around 1600 and comes from Latin. From Old French reaume/realme ("kingdom"), of murky origin, likely a blend of Latin regimen and rēgālis; the modern spelling settled around 1600.

“Realm” is a fairly common word in modern English.

“Realm” has 2 distinct senses listed in this dictionary. The most common is: a kingdom or territory ruled by a monarch or supreme authority.

A kingdom is specifically a territory ruled by a king or queen, while a realm is any territory under a monarch or supreme authority, making it slightly broader and more formal. Realm is also used figuratively for an area of activity or knowledge, as in "the realm of science," where kingdom would sound odd.

Both words can describe an area of activity, knowledge, or influence, and in figurative use they are often interchangeable. Realm leans slightly literary and suggests a broad sphere ("the realm of politics"), while domain often implies ownership, control, or specialism ("that decision is the manager's domain"). Domain also has technical meanings, such as an internet domain, that realm does not share.

Realm sits at the formal or literary end of the scale, especially in its original sense of a monarch's territory, where it appears in legal and ceremonial language. In everyday figurative use, as in "the realm of fantasy," it is common in written English but rarer in casual speech.