A vivid account of the nearly Sisyphean task of compiling a dictionary for a living language ... Ms. Stamper is an engaging guide, and her curiosity about language, science and odd characters animates the book. At times, however, the prose can feel overstuffed, as if mirroring the abundance of the dictionary it celebrates. The narrative wanders through exuberant wordplay and digressions that can become distracting ... Imaginative riffs and historical detours pull the reader well beyond the book’s central thread.