Gross clinical terms
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Blister - Nonspecific term for fluid-filled lesion
Bulla - Fluid-filled lesion>5 mm in greatest dimension
Excoriation - Lesion of traumatic nature with epidermal loss in a generally
linear shape
Lichenification - Leathery thickening of skin with induration and
hyperkeratosis due to chronic mechanical or chemical irritation
Macule - Flat circumscribed area demarcated by color from surrounding tissue
Nodule - Solid raised discrete lesion >5 mm in greatest dimension
Onycholysis - Loosening or loss of nail substance resulting in loss of integrity
Papule - Solid raised discrete lesion <5mm
Plaque - Flat but elevated area, >5 mm
Pustule - Small pus-filled elevated area of the skin with discrete borders
Vesicle - Fluid-filled lesion of <5 mm
Histologic terms
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Acantholysis - Dissolution of intercellular integrity with fragmentation of
epidermis
Acanthosis - Hyperplasia of epidermal prickle cell
Dyskeratosis - Abnormal keratinization occurring prematurely in cells
below the stratum granulosum
Erosion - Loss of epidermis
Exocytosis - Infiltration of epidermis by inflammatory cells
Hyperkeratosis - Thickening of the stratum corneum with excess abnormal
keratin
Parakeratosis - retention of nuclei in the cells of the stratum corneum of the
epidermis, as in psoriasis.
Papillomatosis - Hyperplasia of the papillary dermis and lengthening and/or
widening of the dermal papillae
Spongiosis - Edema limited to the epidermis
Ulceration - Loss of epidermis with variable partial-to-complete loss of dermis