definition of
realm

[1] #1 realm n. [kingdom, land] a domain in which something is dominant; "the untroubled kingdom of reason"; "a land of make-believe"; "the rise of the realm of cotton in the south". wn

[2] #2 realm n. [kingdom] the domain ruled by a king or queen. wn

[3] #3 realm n. [region] a knowledge domain that you are interested in or are communicating about; "it was a limited realm of discourse"; "here we enter the region of opinion"; "the realm of the occult". wn