Intense and uncritical enthusiasm or zeal, typically for a particular cause or belief.

कट्टरता

English Usage: His fanaticism for the team led him to attend every game, regardless of the distance.

Hindi Usage: उसके टीम के प्रति कट्टरता ने उसे हर खेल में जाने के लिए मजबूर किया, चाहे दूरी कितनी भी हो।