The Collaborative International Dictionary of English v.0.48:

Predecessor \Pred`e*ces"sor\ (?; 277), n. [L. praedecessor; prae
   before + decessor one who withdraws from the province he has
   governed, a retiring officer (with reference to his
   successor), a predecessor, fr. decedere: cf. F.
   pr['e]d['e]cesseur. See Decease.]
   One who precedes; one who has preceded another in any state,
   position, office, etc.; one whom another follows or comes
   after, in any office or position.
   [1913 Webster]

         A prince who was as watchful as his predecessor had
         been over the interests of the state.    --Prescott.
   [1913 Webster]

WordNet (r) 3.0 (2006):

predecessor
    n 1: one who precedes you in time (as in holding a position or
         office)
    2: something that precedes and indicates the approach of
       something or someone [syn: harbinger, forerunner,
       predecessor, herald, precursor]

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

parent
mother
predecessor

    The ancestor node in a tree that
   points to the current node (one of its child nodes).

   (2005-09-15)