What does the term 'detrending' refer to in the context of ARIMA?

Detrending refers to the process of removing trends from a dataset to focus on the underlying patterns and improve the accuracy of forecasting models, particularly in the context of ARIMA (AutoRegressive Integrated Moving Average). By adjusting data to eliminate trends, analysts can better identify the stationary components of the time series, allowing the ARIMA model to effectively analyze and predict based on consistent patterns. This step is crucial as ARIMA models assume that the data is stationary; thus, detrending helps to meet that requirement before applying the model for forecasting.