The crossword solution for the term 'KNIGHT's Assistant' is 'PAGE', which is a four-letter word. A PAGE was a young attendant or servant in the medieval period, typically a boy aged 7 to 15 years old. Pages were responsible for a variety of tasks such as running errands, attending their lord, and helping with armor and weapons. They were also expected to learn the skills of knighthood, such as horsemanship, swordsmanship, and chivalry. Pages were often seen as apprentices to knights, and were expected to eventually become knights themselves.