Distinct from Hodgkin lymphoma both morphologically and biologically, non-Hodgkin lymphoma (NHL) is characterized by the absence of Reed-Sternberg cells, can occur at any age, and usually presents as a localized or generalized lymphadenopathy associated with fever and weight loss. The clinical course varies according to the morphologic type. NHL is clinically classified as indolent, aggressive, or having a variable clinical course. NHL can be of B-or T-/NK-cell lineage. The disease is Monarch Disease Ontology id MONDO_0018908 (non-Hodgkin lymphoma). Also known as: NHL, non-Hodgkin's lymphoma, non-Hodgkin's lymphoma (NHL), non-Hodgkins lymphoma.