–adjective
1.
holding fast; characterized by keeping a firm hold (often fol. by of ): a tenacious grip on my arm; tenacious of old habits.
2.
highly retentive: a tenacious memory.
3.
pertinacious, persistent, stubborn, or obstinate.
4.
adhesive or sticky; viscous or glutinous.
5.
holding together; cohesive; not easily pulled asunder; tough.