Definitions of Lesions
There are many specific descriptors in dermatology which are used to communicate among the cognoscenti regarding lesions. Among them are vesicle, tumor, scale, crust exudate, etc. The most basic of nouns related to lesions are papule, plaque and nodule.
Papules are small, less than 1 cm (less than 5mm in my training) and very discrete.
Plaques are broad, raised lesions greater than 1 cm.
Nodules are generally accepted to be greater than 1 cm but less than 2.5 cm, but can include lesions that are up to 5 cm, although that is approaching the range of tumors.
We will have further definitions in our challenge from time to time, but these are the most important.