pits
Small, sharply demarcated depressions in the skin or nail surface.
pityriasiform scale
Delicate and fine scale.
plane
A flat or level surface.
plaque
A discrete, solid, elevated body usually broader than it is thick measuring more than .5 cm in diameter. Plaques may be further classified by shape, size, color, and surface change.

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poikiloderma
An area of variegated pigmentation, atrophy and telangiectasia.

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polycyclic
Formed from coalescing circles, rings, or incomplete rings.

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polygonal
Having many sides.
powdery
Of the nature or consistence of powder or fine loose particles.
pterygium
Scar-like triangular extension of the proximal nail fold tissue and cuticle distally over the nail plate. The nail can become gradually eroded at this point and becomes divided with linear grooves and fragments.
punched-out ulcer
An ulcer with a sharply demarcated edge.
punctate
Dot-like.
purpura
Hemorrhage into skin or mucous membranes which varies in size and ranges in color related to duration. Types of purpura include palpable purpura, ecchymosis, and petechiae.
purpura, palpable
Raised and palpable, nonblanchable, red or violaceous discoloration of skin or mucous membranes due to vascular inflammation in the skin and extravasation of red blood cells.

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purulent
Producing or containing pus.
pustule
A circumscribed elevation that contains pus. Pustules are usually less than .5 cm in diameter.

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