Being tenacious means to CLING to something with determination and perseverance. It is a quality that is often associated with success, as it requires a person to stay focused on their goals and never give up. The crossword solution for the term 'be tenacious' is 'CLING, ' which is a five-letter word. Clinging to something can be seen as an act of tenacity, as it implies that a person is determined to hold onto something despite any obstacles they may face.