Definition of "horizon" []

• The apparent intersection of the earth and sky as seen by an observer. Also called apparent horizon. (noun)
• Astronomy The sensible horizon. (noun)
• Astronomy The celestial horizon. (noun)
• Astronomy The limit of the theoretically possible universe. (noun)
• The range of one's knowledge, experience, or interest. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Also looming on the horizon is the question of a referendum and its timing."
• "And looming on the horizon is the possibility of renewed violence in Sudan on a scale unimaginable even by past experience."
• "Watching the Rockies appear on the horizon is the most majestic site, especially when driving through Kansas."