The term 'overly zealous' is used to describe someone who is excessively enthusiastic or passionate about something. This can be seen in the crossword solutions for the term: AVID (4 letters), RABID (5 letters), FANATICAL (9 letters), and MANIACAL (8 letters). Someone who is AVID is eager and enthusiastic, while someone who is RABID is FANATICAL and frenzied. FANATICAL implies an extreme level of enthusiasm, and MANIACAL suggests a wild and uncontrolled passion. All of these words are used to describe someone who is overly zealous.