The rapid developments in the fields of telecommunication,sensor data,financial applications,analyzing of data streams,and so on,increase the rate of data arrival,among which the data mining technique is considered a vital process.The data analysis process consists of different tasks,among which the data stream classification approaches face more challenges than the other commonly used techniques.Even though the classification is a continuous process,it requires a design that can adapt the classification model so as to adjust the concept change or the boundary change between the classes.Hence,we design a novel fuzzy classifier known as THRFuzzy to classify new incoming data streams.Rough set theory along with tangential holoentropy function helps in the designing the dynamic classification model.The classification approach uses kel fuzzy c-means (FCM) clustering for the generation of the rules and tangential holoentropy function to update the membership function.The performance of the proposed THRFuzzy method is verified using three datasets,namely skin segmentation,localization,and breast cancer datasets,and the evaluated metrics,accuracy and time,comparing its performance with HRFuzzy and adaptive k-NN classifiers.The experimental results conclude that THRFuzzy classifier shows better classification results providing a maximum accuracy consuming a minimal time than the existing classifiers.