Elmer-speak
He nearly always vocalised consonants and, pronouncing them as instead (a trait that also characterized Tweety Bird) when he would talk in his slightly raspy voice. This trait was prevalent in the Elmer's Candid Camera and Elmer's Pet Rabbit cartoons, where the writers would give him exaggerated lines such as, "My, that weawwy was a dewicious weg of wamb." to further exaggerate his qualities as a harmless nebbish. That characteristic seemed to fit his somewhat timid and childlike persona. And it worked. The writers often gave him lines filled with those letters, such as doing Shakespeare's Romeo as "What wight thwough yonduh window bweaks!" or Wagner's Ride of the Valkyries as "Kiww the wabbit, kiww the wabbit, kiww the wabbit...!" or "The Beautifuw Bwue Danube, by Johann Stwauss", Stage Door Cartoon's line "Oh, you dubbuh-cwossing wabbit! You tweachewous miscweant!" or the name of actress "Owivia deHaviwwand". Elmer's speech impediment is so well known that Google allows the user to change the search engine language to "Elmer Fudd." Comedian Robin Williams often refers to the impediment as "Fudd syndrome" whenever he accidentally slips up and replaces an 'l' or 'r' with a 'w' sound in a word.
Part of the joke is that Elmer is presumably incapable of pronouncing his own first name correctly. Occasionally Elmer would properly pronounce an r or l sound, depending on whether or not it was vital for the audience to understand what the word was. (For example, in 1944's The Old Grey Hare, he clearly pronounces the r in the word "picture".) Usually, Elmer pronounces the 'r's and 'l's when one of those letters is in the last syllable of the word (such as "rascal", which he says as "wascal"). This doesn't occur in one-syllable words like "last" ("wast") or in common words like "hello" ("hewwo").
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