The pen—or, as Nick and his friends prefer to call it, the frindle—serves as a motif reflecting the power of language. The pen is an everyday object, but simply by applying new language to it, masses of people associate a new word with the common object. Through most of the book, characters refer to frindles more conceptually than concretely; the frindle movement emphasizes the word itself rather than the physical object it represents. However, though Nick’s decision to call a pen a frindle appears coincidental, an object with inextricable links to language is deliberately chosen. Pens, as a tool, document a wealth of knowledge. The image of a pen suggests that the word’s legacy will endure, preserved in ink for generations to use. Mrs. Granger finally declares the conflict “over” when ink records Nick’s word in the ultimate authority of language: the dictionary.

Though the motif focuses primarily on the word itself, its narrative significance is incorporated as well. Two ostensibly random pens are established: first, Mrs. Granger’s favorite writing utensil, a maroon fountain pen with a blue cap; second, the gold ballpoint pen that Nick discovers on the roadside when he conceives the word frindle.