Background: There is limited research on how patients prefer physicians to communicate about the topic of obesity, and there is even less understanding of which terms physicians most commonly use. Methods: In this cross-sectional, nonrandom sampling study, patients who were seeking treatment for weight loss rated the desirability of 12 terms to describe excess weight, and physicians rated the likelihood with which they would use those terms during clinical encounters. Participants rated terms on a 5-point scale, with -2 representing "very undesirable" or "definitely would not use" and +2 representing "very desirable" or "definitely would use." Results: Patients (n = 143; mean age, 46.8 years; mean body mass index, 36.9 kg/m2) rated "weight" (mean ± SD) as the most desirable term (1.13 ± 1.10), although it did not significantly differ from 5 other terms provided. They rated "fatness" (-1.30 ± 1.22) as the most undesirable term, although this rating did not differ significantly from 4 other terms. Physicians affiliated with a community-based medical school (n = 108; mean age, 48.8 years; 79.6% primary care specialty) were most likely to use "weight" (1.42 ± 0.89), which was significantly different from ratings for all other terms. They were least likely to use "fatness" (-1.74 ± 0.59), although this rating did not differ significantly from 3 other terms. Conclusion: Physicians generally reported that they use terminology that patients had rated more favorably, and they tend to avoid terms that patients may find undesirable. Understanding the preferences and terminology used by patients and physicians is an important initial step to ensure that communications related to obesity and weight loss are efficient and effective.