The Collaborative International Dictionary of English v.0.48:

Planner \Plan"ner\, n.
   One who plans; a projector.
   [1913 Webster]

WordNet (r) 3.0 (2006):

planner
    n 1: a person who makes plans [syn: planner, contriver,
         deviser]
    2: a notebook for recording appointments and things to be done,
       etc.

Moby Thesaurus II by Grady Ward, 1.0:

61 Moby Thesaurus words for "planner":
   a, ancestors, apprentice, architect, artificer, artist, author,
   begetter, beginner, builder, conceiver, constructor, contriver,
   craftsman, creator, designer, developer, deviser, discoverer,
   effector, engenderer, engineer, enterpriser, entrepreneur,
   executor, executrix, father, founder, framer, generator, grower,
   inaugurator, industrialist, initiator, instigator, institutor,
   introducer, inventor, journeyman, maker, manufacturer, master,
   master craftsman, mother, organizer, originator, past master,
   precursor, prime mover, producer, projector, promoter, raiser,
   realizer, shaper, sire, smith, strategian, strategist, tactician,
   wright



The Free On-line Dictionary of Computing (30 December 2018):

PLANNER

   A language for writing theorem provers by Carl Hewitt
    MIT 1967.  Never fully implemented.

   CONNIVER was an outgrowth of PLANNER and microPLANNER a
   subset.  PLASMA is a PLANNER-like system modelled on
   Actors.  See also POPLER, QLISP, Scheme.

   ["PLANNER: A Language for Proving Theorems in Robots", Carl
   Hewitt, Proc IJCAI-69, Wash DC, May 1969].