What condition is characterized by both dilation of the pupil and loss of accommodation?

The condition that is characterized by both dilation of the pupil and loss of accommodation is mydriasis. Mydriasis simply refers to the dilation of the pupils, which can occur due to various factors such as the use of certain medications, emotions, or light conditions. In addition to pupil dilation, a loss of accommodation is often observed, which affects the eye's ability to focus on near objects. This loss is due to the ciliary muscle's inability to contract effectively, which can occur alongside mydriasis when the pupil is dilated.

In the context of the other options, glaucoma typically results in increased intraocular pressure that can lead to visual disturbances but does not characteristically present with both dilated pupils and loss of accommodation. Scotoma refers to a partial loss of vision or a blind spot in the visual field, while nystagmus involves involuntary eye movements. Neither of these conditions primarily involves pupil dilation or the loss of accommodation in the way that mydriasis does. Thus, mydriasis is recognized for its defining characteristics of pupil dilation accompanied by the loss of the eye's focusing ability.