Rarity/ˈrerəti/ Definition 1 of 3Pro Tip 1/3Seldom Seen Emphasizes the rare occurrence of events or items in everyday life. A four-leaf clover is a rarity you might come across if you’re lucky. Pro Tip 2/3Unexpected Surprise Suggests a positive connotation that the rare instance is a delightful surprise. Finding a friend with such loyalty is a true rarity. Pro Tip 3/3Natural Oddities Refers to rare natural phenomena that might be scientifically interesting. Discovering a new, rare species of bird is a rarity for ornithologists.