Realm \Realm\, n. [OE. realme, ream, reaume, OF. reialme, roialme, F. royaume, fr. (assumed) LL. regalimen, from L. regalis royal. See Regal.]

1. A royal jurisdiction or domain; a region which is under the dominion of a king; a kingdom.

The absolute master of realms on which the sun perpetually alone. --Motley.

2. Hence, in general, province; region; country; domain; department; division; as, the realm of fancy.

Source: Webster's Revised Unabridged Dictionary (1913)