Background: Nurses work in situations of complex care that require high-level clinical reasoning skills. In the literature, clinical reasoning is often confused with other concepts and has no consensual definition. Aim: To conduct a concept analysis of nurses’ clinical reasoning in order to clarify, define, and distinguish it from other concepts, as well as to better understand clinical reasoning. Method: Rodgers’s method of concept analysis was used to analyze clinical reasoning, following a review of articles whose keywords included clinical reasoning, concept analysis, nurse, critical care, and decision making. Results: The use of cognition and cognitive strategies, a systematic approach of analysis and data interpretation, and generating hypotheses and alternatives are all attributes of clinical reasoning. The antecedents are experience, knowledge, memory, cues, intuition, and data collection. The consequences are decision making, action, clues, and problem solving. Conclusion: This concept analysis helped to define clinical reasoning, to distinguish it from other concepts used synonymously, and to guide future research.