Xanthoma
Yellowish firm nodules in the skin frequently indicating underlying disease, such as diabetes, disorder of fats (lipid disorder or hyperlipidemia), or other conditions.
A xanthoma is a kind of harmless growth of tissue.
Under the microscope, a xanthoma can be seen to be composed of lipid-laden foam cells.
These cells, termed histiocytes, contain lipid material in their cytoplasm (the nonnuclear zone of the cell).
The word 'xanthoma' is made up of 'xanth-' from the Greek roots 'xanthos' (yellow) and 'oma' (swelling) = a yellow swelling.
A xanthoma is a circumscribed yellow swelling, a yellowish nodule.