Purpose of Review <p>Hidradenitis suppurativa (HS) is a heterogeneous, chronic, inflammatory disease with limited treatment options requiring a complex network of interdisciplinary teams. Diagnosis is clinical, relying on the typical morphology, characteristic locations and recurrence of lesions. Initial recognition and longitudinal surveillance of lesions can be exceptionally challenging, and there is not yet a globally accepted nomenclature for the unique morphologies found in HS. Consensus on descriptive terms used for HS would improve diagnostic accuracy, enable reliable comparison of clinical trial data, facilitate clear interdisciplinary communication, enhance our understanding of underlying immunologic mechanisms, and support the development of phenotype classifications to promote individualized treatment plans.</p> Recent Findings <p>Although several glossaries have been proposed to standardize HS nomenclature, none have been universally accepted for widespread use. Phenotypic classifications are currently being developed. However, with attempts to develop these phenotypic classifications, several morphologies have emerged that are not accurately represented by previous definitions. Additionally, distinct molecular and immunologic profiles in patients with certain HS lesions suggest specific pathomechanisms that, with further characterization, may allow clinical examination to guide targeted therapy.</p> Summary <p>In this paper, we address this unmet need and present a review of the morphological features of HS described in the literature. In addition, we propose a convincing definition for previously undefined types of hidradenitis lesions, such as pyoderma gangrenosum-like lesions, eroded nodules (also referred to as pyogenic granuloma-like lesions), cord-like scarring, cribriform scarring, and involuted lesions.</p>