Medical Dictionary: Glossary (X)

What is X-ray?

High-energy radiation used in low doses to make images that help to diagnose diseases and in high doses to treat cancer.

What is xanthoma?

Yellowish firm nodules in the skin frequently indicating underlying disease, such as diabetes, disorder of fats etc.

What is xerostomia?

Dry mouth. Xerostomia can be associated with systemic diseases,
such as Sjogren’s syndrome, systemic lupus erythematosus, and rheumatoid arthritis; or it can be a side effect of medication and poor dental hygiene.

What is xerosis?

Abnormal dryness of the skin, mucous membranes, or conjunctiva (xerophthalmia).

What is xanthelasma?

Tiny (1-2 mm) yellowish plaques that are slightly raised on the skin surface of the upper or lower eyelids.

What is xeroderma?

Abnormally dry skin. Xeroderma can be caused by a deficiency of vitamin A, systemic illness (such as hypothyroidism or Sjogren’s syndrome), overexposure to sunlight, and medication.

What is xiphoid process?

The lower part of the breastbone. The xiphoid process has no particular function and ranges in size from miniscule to several inches in length.

What is X-linked?

A gene on the X chromosome . An X-linked disorder is associated with or caused by a gene on the X chromosome.