La presbicia (del griego πρέσβυς 'anciano'), también denominada vista cansada, es un defecto ocular asociado a la edad que aparece generalmente entre los 40-45 años y ocasiona dificultad para ver de cerca. Se debe a la reducción del poder de acomodación del ojo que provoca disminución de la capacidad para enfocar objetos cercanos.

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Presbyopia is a condition associated with aging of the eye that results in progressively worsening ability to focus clearly on close objects. Symptoms include a hard time reading small print, having to hold reading material farther away, headaches, and eyestrain. Different people will have different degrees of problems. Other types of refractive errors may exist at the same time as presbyopia. Presbyopia is a natural part of the aging process. It is due to hardening of the lens of the eye causing the eye to focus light behind rather than on the retina when looking at close objects. It is a type of refractive error along with nearsightedness, farsightedness, and astigmatism. Diagnosis is by a eye exam. Treatment is typically with eye glasses. The eyeglasses used have higher focusing power in the lower portion of the lens. Off the shelf reading glasses may be sufficient for some. Anyone over the age of 35 is at risk for developing presbyopia and all people become affected to some degree. The condition was mentioned as early as the writings of the Ancient Greek, Aristotle. Glass lens first came into use for the problem in the late 13th century. The word is from the Greek πρέσβυς (presbys) meaning "old man" and ὤψ (ops) meaning to "see like".

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