1. the lens or group of lenses in an optical instrument (such as a microscope or telescope) that is closest to the eye and through which the magnified image is viewed

Examples

• She adjusted the eyepiece of the microscope to bring the specimen into sharp focus.
• The telescope's eyepiece magnifies the distant stars so they appear much brighter.
• A high-quality eyepiece is essential for comfortable viewing through a microscope.
• He looked through the eyepiece and saw the tiny cells clearly.
• The eyepiece can be replaced with different magnifications depending on your needs.
• When using a microscope, always start with the lowest magnification eyepiece.