Having parts apt to adhere to each other; cohesive; tough; as, steel is a tenacious metal; tar is more tenacious than oil
If you are tenacious, you are very determined and do not give up easily. He is regarded at the BBC as a tenacious and persistent interviewer. + tenaciously te·na·cious·ly In spite of his illness, he clung tenaciously to his job
Holding fast, or inclined to hold fast; inclined to retain what is in possession; as, men tenacious of their just rights
If you describe something such as an idea or belief as tenacious, you mean that it has a strong influence on people and is difficult to change or remove. a remarkably tenacious belief that was to dominate future theories of military strategy. = deep-seated