Realm
Part of speech: noun
Definition: An abstract sphere of influence, real or imagined. The domain of a certain abstraction. A territory or state, as ruled by a specific power, and particularly those territories ruled by a king.
Example sentence: The meaning of life is not to be discovered only after death in some hidden, mysterious realm; on the contrary, it can be found by eating the succulent fruit of the Tree of Life and by living in the here and now as fully and creatively as we can.
Kingdom
Part of speech: noun
Definition: A nation having as supreme ruler a king and/or queen.A rank in the classification of organisms, below domain and above phylum; a taxon at that rank (e.g. the plant kingdom, the animal kingdom)
Example sentence: God's plan for enlarging His kingdom is so simple - one person telling another about the Savior. Yet we're busy and full of excuses. Just remember, someone's eternal destiny is at stake. The joy you'll have when you meet that person in heaven will far exceed any discomfort you felt in sharing the gospel.