A eunuch is a man who has had his testicles removed. a man whose testicles have been removed, especially someone who guarded a king's wives in some Eastern countries in the past (eunuchus, from eunouchos, from eune + echein ). Castrated human male. From remote antiquity on, eunuchs were employed in the Middle East and China as guards and servants in harems or other women's quarters and as chamberlains to kings. The eunuchs' confidential position frequently enabled them to exercise an important influence over their royal masters. Many of the patriarchs of Constantinople during Byzantine times were eunuchs. Eunuch advisers disappeared as a class only with the end of the Ottoman Empire. See also castrato