persistent

Etymology

From Latin persistentem, present participle of persistō (“continue steadfastly”). Synchronically analyzable as persist + -ent.

adj

1. Obstinately refusing to give up or let go.
   She has had a persistent cough for weeks.
   The most persistent tormentor was Alex Oxlade-Chamberlain, who scored a hat-trick in last month’s corresponding fixture in Iceland. His ability to run at defences is instantly striking, but it is his clever use of possession that has persuaded some shrewd judges that he is an even better prospect than Theo Walcott. November 10, 2011, Jeremy Wilson, “England Under 21 5 Iceland Under 21 0: match report”, in Telegraph
2. Insistently repetitive.
   There was a persistent knocking on the door.
3. Indefinitely continuous.
   There have been persistent rumours for years.
4. (botany) Lasting past maturity without falling off.
   Pine cones have persistent scales.
5. (computing) Of data or a data structure: not transient or temporary, but remaining in existence after the termination of the program that creates it.
   Once written to a disk file, the data becomes persistent: it will still be there tomorrow when we run the next program.
6. (mathematics) Describing a fractal process that has a positive Brown function
7. (mathematics, stochastic processes, of a state) non-transient.