For the writer (seller) of a call option, it represents an obligation to sell the underlying security at the strike price if the option is exercised. The call option writer is paid a premium for taking on the risk associated with the obligation.
Definition of gonad. : a reproductive gland (as an ovary or testis) that produces gametes.
The use of a lead shield for gonadal protection is very typical in most x-ray departments and is typically mandated by regulations administered by the state you are in. Usually the only shielding for the patient that is required is gonadal shielding if the gonads are in, or near, the primary x-ray beam.