The Collaborative International Dictionary of English v.0.48:

Persistent \Per*sist"ent\, a. [L. persistens, -entis, p. pr. of
   persistere. See Persist.]
   1. Inclined to persist; having staying qualities; tenacious
      of position or purpose.
      [1913 Webster]

   2. (Biol.) 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.
      [1913 Webster]

WordNet (r) 3.0 (2006):

persistent
    adj 1: never-ceasing; "the relentless beat of the drums" [syn:
           persistent, relentless, unrelenting]
    2: continually recurring to the mind; "haunting memories"; "the
       cathedral organ and the distant voices have a haunting
       beauty"- Claudia Cassidy [syn: haunting, persistent]
    3: retained; not shed; "persistent leaves remain attached past
       maturity"; "the persistent gills of fishes" [syn:
       persistent, lasting] [ant: caducous, shed]
    4: stubbornly unyielding; "dogged persistence"; "dour
       determination"; "the most vocal and pertinacious of all the
       critics"; "a mind not gifted to discover truth but tenacious
       to hold it"- T.S.Eliot; "men tenacious of opinion" [syn:
       dogged, dour, persistent, pertinacious, tenacious,
       unyielding]

The Free On-line Dictionary of Computing (19 January 2023):

persistence
persistent

   1.  A property of a programming language where
   created objects and variables continue to exist and retain
   their values between runs of the program.

   2.  The length of time a phosphor dot on the screen
   of a cathode ray tube will remain illuminated after it has
   been energised by the electron beam.  Long-persistence
   phosphors reduce flicker, but generate ghost-like images that
   linger on screen for a fraction of a second.

   (1994-11-09)