Rabbit rabbit rabbit

"Rabbit rabbit rabbit" is a superstition in some English-speaking countries where a person says "rabbit", "rabbits" or "white rabbits" upon waking on the first day of a month, to ensure good luck for the rest of it.
The origin of the superstition is unknown, though it was recorded in Notes and Queries as being said by children in 1909:
In response to this note another contributor said that his daughter believed that the outcome would be a present, and that the word must be spoken up the chimney to be most effective; another pointed out that the word rabbit was often used in expletives, and suggested that the superstition may be a survival of the ancient belief in swearing as a means of avoiding evil. People continue to express curiosity about the origins of this superstition and draw upon it for inspiration in making calendars suggestive of the Labors of the Months, thus linking the rabbit rabbit superstition to seasonal fertility.
It appeared in a work of fiction in 1922:
Chapter 1 of the Trixie Belden story The Mystery of the Emeralds (1962) is titled "Rabbit! Rabbit!" and discusses the tradition:
In the United States, the tradition appears especially well known in northern New England although, like all folklore, determining its exact area of distribution is difficult. The superstition may be related to the broader belief in the rabbit or hare being a "lucky" animal, as exhibited in the practice of carrying a rabbit's foot for luck. Rabbits have not always been thought of as lucky, however. In the 19th century, for example, fishermen would not say the word while at sea; in South Devon, to see a white rabbit in one's village when a person was very ill was regarded as a sure sign that the person was about to die.
During the mid-1990s, the American children's cable channel Nickelodeon helped popularize the superstition in the United States as part of its "Nick Days", where during commercial breaks, it would show an ad about the significance of the current date, whether it be an actual holiday, a largely uncelebrated unofficial holiday, or a made-up day if nothing else is going on that specific day (the latter would be identified as a "Nickelodeon holiday"). Nickelodeon would promote the last day of each month as "Rabbit Rabbit Day" and remind kids to say it the next day unless the last day of that specific month was an actual holiday, such as Halloween or New Year's Eve. This practice stopped by the late 1990s.
There is another folk tradition that may use a variation of "Rabbit", "Bunny", "I hate/love Grey Rabbits" or "White Rabbit" to ward off smoke that the wind is directing into your face when gathered around a campfire. It is thought that this tradition may be related to the practice of invoking the rabbit on the first of the month. Others conjecture that it may originate with a North American First Nation story about smoke resembling rabbit fur. This tradition may be more of a social tradition in a group setting than a genuine belief that specific words will change the wind direction and may be more of a childhood tradition than an adult one. Children have sometimes adapted from Rabbit to "Pink Elephant" or other comical derivatives. Because of this more mutable usage, the historical record is even more scarce than other more static meanings.
As with most folklore, which is traditionally spread by word of mouth, there are numerous variants of the superstition, sometimes specific to a certain time period or region.