Abbreviations are both ubiquitous in clinical documentation and frequently misinterpreted. This cross-sectional Israeli study found that only 1.2% of physicians could understand 50% or more of the abbreviations in ophthalmologists' notes. Israeli physicians document in Hebrew, but ophthalmologists there favor English abbreviations. The authors suggest that use of abbreviations should be discouraged due to the potential for misinterpretations to affect patient care.