The Collaborative International Dictionary of English v.0.48:

Reaper \Reap"er\ (r[=e]p"[~e]r), n.
   1. One who reaps.
      [1913 Webster]

            The sun-burned reapers wiping their foreheads.
                                                  --Macaulay.
      [1913 Webster]

   2. A reaping machine.
      [1913 Webster]

WordNet (r) 3.0 (2006):

reaper
    n 1: someone who helps to gather the harvest [syn: harvester,
         reaper]
    2: Death personified as an old man or a skeleton with a scythe
       [syn: Grim Reaper, Reaper]
    3: farm machine that gathers a food crop from the fields [syn:
       harvester, reaper]

Moby Thesaurus II by Grady Ward, 1.0:

44 Moby Thesaurus words for "reaper":
   Bauer, agriculturalist, agriculturist, agrologist, agronomist,
   coffee-planter, collective farm worker, crofter, cropper,
   cultivator, dirt farmer, dry farmer, farm laborer, farmer,
   farmhand, gentleman farmer, granger, grower, harvester, harvestman,
   haymaker, husbandman, kibbutznik, kolkhoznik, kulak, muzhik,
   peasant, peasant holder, picker, planter, plowboy, plowman, raiser,
   rancher, ranchman, rustic, sharecropper, sower, tea-planter,
   tenant farmer, tiller, tree farmer, truck farmer, yeoman



The Jargon File (version 4.4.7, 29 Dec 2003):

reaper
 n.

    A prowler that removes files. A file removed in this way is said to have
    been reaped.


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

reaper

   A prowler that GFRs files.  A file removed in this way is
   said to have been "reaped".

   [Jargon File]