cycloplegic /sī′kləplē″jik/ , 1. adj., pertaining to a drug or treatment that causes paralysis of the ciliary muscles of the eye. 2. n., one of a group of anticholinergic drugs used to paralyze the ciliary muscles of the eye for ophthalmological examination or surgery. Any of the cycloplegics may cause adverse effects in persons sensitive to anticholinergics.