Because we communicate mainly through words, it is important that terms be understood in the same manner by all readers. Unfortunately, the study of the patellofemoral joint is complicated by the use of expressions that hold different meanings for different readers. Ideally, the community of musculoskeletal physicians should agree on a single definition of terms, but until then, authors and speakers should define their terms clearly. Some terms, such as chondromalacia and patellofemoral syndrome, should be abandoned altogether. I propose a glossary of confusing terms pertaining to the patellofemoral joint, the various interpretations of these terms, and possible resolutions of these conflicts. Words and terms included in this review include chondromalacia, patellofemoral syndrome, anterior knee pain, subluxation, malalignment, proximal realignment, Roux procedure, and "normal."