There are a variety of antonyms for the word "slowwittednesses," which refers to the state of being mentally slow, sluggish, or dull. Some possible antonyms include "sharpness," "quickness," "intelligence," "agility," "cleverness," "innovativeness," "astuteness," and "wit." These terms describe individuals with sharp minds who are quick to learn, inventive, insightful, and witty. Antonyms also include phrases such as "mental acuity," "cognitive ability," "high IQ," and "mental agility." Therefore, antonyms for "slowwittednesses" describe individuals with high mental capacity and who can complete tasks more efficiently and competently.