A pelican who is often mispronounced as "Dr. Nitwit", which he hates being called. In his segments, he presents his assistant Watson to a word which he thinks is the only one that has a certain letter pattern, but when Watson says a short speech with a word that has the same meaning, Dr Nitwhite types it down on his computer and becomes upset.
- mom, pop, wow (Episode 02: The Lost Rock, Episode 13: Pandora's Box, Episode 30: Be Bop, Episode 77: Sylvester and the Magic Pebble / I Miss You, Stinky Face)
- yes, yet, let, bet (Episode 06: The Hopping Hen, Episode 83: Yo! Yes?/Very Loud, Very Big, Very Metal)
- boo, cool, fool, toodle-oo, oops (Episode 07: Touching the Moon)
- in, it (Episode 08: The Boy Who Cried Wolf)
- fly, my, why, cry, try (Episode 15: There's a Fly in My Soup, Episode 79: Earl's Too Cool / When I Was Five)
- flat, that, scat, drat (Episode 31: The Sad Dad, Episode 60: You Can't Catch Me!)
- bun, fun, run (Episode 44: Bug Beard)