Mydriatic drugs are medications that are used to dilate the pupil of the eye. Some of the synonyms of the word 'mydriatic drug' include pupillary dilators, dilating agents, and cycloplegics. Pupillary dilators are substances that increase the size of the pupil, allowing more light to enter the eye, and dilating agents refer to any chemical agent that causes dilation of the pupil. Cycloplegics are drugs that paralyze the ciliary muscles of the eye and prevent the eye from focusing, and, as a result, dilate the pupil. These drugs are commonly used in eye examinations as they allow the ophthalmologist to view the retina and other structures in the eye more clearly.