Prunella is a tall, 9-year-old anthropomorphic poodle with tan (yellow from the show's sixteenth season onward) skin, black dots with no sclerae for eyes, curly brown (auburn from season sixteen onward) hair, and a pink nose. Her casual outfit consists of a short turquoise dress with white buttons, a turquoise hair bow, white socks and auburn shoes with light brown soles.
- A purple shirt with frilled sleeves, a purple hair bow, black pants and white shoes with light brown soles (only seen in the printable "Groove It" cards on the PBS Kids website)
- A blue sleeping dress with white star and blue half-moon designs.
- Formal wear consisting of a light blue dress with white strings tied together on the chest area, white knee-high socks and light brown sandals.
- Winter wear that consists of a blue dress with lighter blue frills at the bottom and a white fur collar around the neck, an orange and violet knit cap with a yellow bob, and brown boots with white socks.
- A dark blue sweater with a white collar and and a light blue skirt.
- A white karate uniform.
- A yoga outfit that consists of a light blue top, dark blue pants and two violet hair ribbons.
- A black skeleton costume for Halloween.
- A grebe costume.
- A white painter's smock.
- A fortuneteller's outfit that consists of a dark blue hood, a pinkish-purple and blue dress, and a green coat.
- Swimwear that consists of a white swimming cap decorated with a blue flower, and a one-piece swimsuit that has darker blue parts around the arms and legs.
Personality and traits
Prunella has an interest in reading, and she especially likes the fictional book series Henry Skeever (a parody of Harry Potter). She is also superstitious and has an interest in paranormal phenomena and fortune-telling. She is fairly intelligent as well.
Like Muffy Crosswire (whom Prunella occasionally hangs out with), she can sometimes be a little selfish and snobby, often thinking that she is better at everything than the third grade students at Lakewood Elementary just because she's their senior by one year. Also like Muffy, she hates to get her clothes dirty and wants the fanciest ones possible; in the episode "Prunella's Prediction", she become jealous of Muffy because she bought a fancy pair of pants called "Flash Pants".
Prunella likes telling the third graders stories about her own time in third grade, although these stories are usually exaggerated, like the one where she claimed that the teacher, Nigel Ratburn, ate nails for breakfast.
In the episode "Prunella the Packrat", it is revealed that she has a hoarding problem, as when she has to empty her closet, she tries to save items that she considers important to herself.
- Prunella's surname was inspired by Jacqui Deegan, one of the TV show's writers.
- The show's animators have mistakenly placed her in Nigel Ratburn's classroom several times. This is because she used to be in his class when she was in third grade.
- Despite the shape of her ears and not having whiskers, official sources sometimes mistakenly refer to Prunella as a rat.