persistence

From Middle French persistance.

• (UK) IPA^(key): /pəˈsɪst(ə)ns/

• Audio (Southern England):

  (file)

persistence (countable and uncountable, plural persistences)

1. The property of being persistent.
   • 1971, Gwen White, Antique Toys And Their Background, page 182:

     The Thaumatrope was based on the persistence of vision. The disc of card was rotated so rapidly by means of threads attached to it that the eye saw both sides of the card simultaneously.

   You've got to admire her persistence. She's asked him out every day for a month even though she keeps turning him down.

2. (computer science) Of data, the property of continuing to exist after the termination of the program.

   Once written to a disk file, the data has persistence: it will still be there tomorrow when we run the next program.

3. (meteorology) Continuation of the previous day's weather (particularly temperature and precipitation statistics).
4. (mathematics) The number of times an operation can be iteratively applied to a number before it reaches a permanently constant state.

   The persistence of the number 39 under the operation of multiplying the digits of the number is three, because 3x9 = 27, 2x7 = 14, and 1x4 = 4, and no further iterations will change the number again.

• persistency
• See also Thesaurus:obstinacy
• See also Thesaurus:perseverance