D defs.my
Entry 2 senses Webster, 1913

Persistent

/pẽrs-ĭs'-tənt/ · Per·sist·ent · IPA /pɚˈsɪstənt/
01 a. Inclined to persist; having staying qualities; tenacious of position or purpose.
  1. 1.
    Inclined to persist; having staying qualities; tenacious of position or purpose.
  2. 2.
    Remaining beyond the period when parts of the same kind sometimes fall off or are absorbed; permanent; as, persistent teeth or gills; a persistent calyx; -- opposed to deciduous, and caducous.(Biol.)