Orthoepy
In medicine, rhotacism is the inability or difficulty in pronouncing the sound r. In English, the most common occurrence of this type is a pronunciation perceived as closer to . The Looney Tunes character Elmer Fudd is notorious for his exaggerated rhotacistic speech, as in, "Be vewwy quiet: I'm hunting wabbits." The cartoon character Homestar Runner talks in much the same way. Another example is the depiction of Pontius Pilate in Monty Python's Life of Brian. In the Only Fools and Horses episode Stage Fright, a singer's rhotacism is a central plot device. In popular culture, examples include Barry Kripke (from the Big Bang Theory), Roy Hodgson, Matt Bellamy, Jonathan Ross, Frank Muir, Sister Wendy Beckett, Lucy Worsley, Terry Jones, and the politician Roy Jenkins. Other examples are interviewer Barbara Walters, actress Kay Francis and Bradley Welling.
Rhotacism is more common among speakers of languages that have a trilled R, such as Swedish (except in the landscapes of Skåne, Halland, Blekinge, Öland and southern Småland), Finnish, Italian, Polish, and Spanish. This sound is usually the last one a child masters. Some people never learn to produce it; they substitute other sounds, such as the velar approximant, the uvular approximant, and the uvular trill (often called "French R").
Many speech pathologists call this problem de-rhotacization, because the sounds lose their rhotic quality rather than becoming rhotic.
Read more about this topic: Rhotacism