Final answer:
Accommodation is the term that describes the ability of the eye to focus on close objects, achieved by changing the shape of the lens. This process is crucial for nearsighted individuals to see clearly at short distances, and corrective lenses may be required to achieve proper distant vision.
Step-by-step explanation:
The term that describes the ability to focus for close vision, specifically under 20 feet, is accommodation. Accommodation refers to the eye's ability to change its focus from distant to near objects. It is the process by which the lens of the eye changes its shape to focus light on the retina from objects at various distances. This adjustment in lens shape is necessary for producing a clear image on the retina when looking at objects up close.
When considering the application of this term to a practical situation, such as a nearsighted person or someone with normal vision trying to view objects at short distances, it's important to mention how vision correction methods like glasses or contact lenses can play a role. For instance, a very myopic person might need a contact lens with a certain power to correct their distant vision by shifting the focal point onto the retina.