Objective Describe the terms used in written records of patients' progress by nurses. Methods Descriptive research with a quantitative method that used a software to extract terms related to 148,200 nursing documentations of patient's progress, from 2010 to 2012, in a university hospital in Curitiba - Paraná. The terms were normalized, if appropriate, in spelling, gender, number and tense; then corpus of 2.638 terms was classified for analysis. Results There were problems related to the identification of the records; the use of trade names for designating artifacts used in the nursing practice; unconventional acronyms and abbreviations; and colloquial terms. Records of terms contained in standardized language of nursing diagnoses were found. Conclusion The language used by nurses is heterogeneous. There is a tendency to use terms of specialized language, even when there is no formal terminology standardization in the institution.