The Collaborative International Dictionary of English v.0.48:

Sift \Sift\, v. t. [imp. & p. p. Sifted; p. pr. & vb. n.
   Sifting.] [AS. siftan, from sife sieve. [root]151a. See
   Sieve.]
   1. To separate with a sieve, as the fine part of a substance
      from the coarse; as, to sift meal or flour; to sift
      powder; to sift sand or lime.
      [1913 Webster]

   2. To separate or part as if with a sieve.
      [1913 Webster]

            When yellow sands are sifted from below,
            The glittering billows give a golden show. --Dryden.
      [1913 Webster]

   3. To examine critically or minutely; to scrutinize.
      [1913 Webster]

            Sifting the very utmost sentence and syllable.
                                                  --Hooker.
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            Opportunity I here have had
            To try thee, sift thee.               --Milton.
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            Let him but narrowly sift his ideas.  --I. Taylor.
      [1913 Webster]

   To sift out, to search out with care, as if by sifting.
      [1913 Webster]

WordNet (r) 3.0 (2006):

sift
    v 1: move as if through a sieve; "The soldiers sifted through
         the woods"
    2: separate by passing through a sieve or other straining device
       to separate out coarser elements; "sift the flour" [syn:
       sift, sieve, strain]
    3: check and sort carefully; "sift the information" [syn:
       sieve, sift]
    4: distinguish and separate out; "sift through the job
       candidates" [syn: sieve, sift]

Moby Thesaurus II by Grady Ward, 1.0:

150 Moby Thesaurus words for "sift":
   air, analyze, appraise, assess, assort, bolt, canvass, catalog,
   categorize, choose, choose out, clarify, class, classify, clear,
   collate, comb, comment upon, consider, contradistinguish,
   controvert, cordon, cordon off, cull, cull out, deal with, debate,
   decide between, decrassify, deliberate, deliberate upon,
   delve into, demarcate, demark, depurate, differentiate, dig into,
   discourse about, discriminate, discuss, distill, distinguish,
   divide, draw the line, edulcorate, elute, essentialize, evaluate,
   examine, excerpt, exchange views, explore, extract, factor, fathom,
   filter, filtrate, gauge, ghettoize, gin, glean, go into, gradate,
   grade, group, handle, handpick, identify, indagate, inquire into,
   insulate, investigate, isolate, keep apart, keep aside,
   knock around, lay aside, leach, lixiviate, look into,
   make a selection, mark the interface, pass under review, peer into,
   percolate, pick, pick out, plumb, poke into, probe, prospect,
   pry into, purify, put aside, quarantine, rank, rap, reason,
   reason about, reason the point, rectify, refine, review, riddle,
   screen, screen out, scrutinize, search into, seclude, segregate,
   select, separate, set a limit, set apart, set aside, set off,
   sever, severalize, sieve, sieve out, sift out, single out, size,
   sort, sort out, sound, spiritualize, split hairs, strain, study,
   subdivide, sublimate, sublime, subordinate, subtilize, take up,
   talk, talk about, talk of, talk over, thrash, thrash out, thresh,
   thresh out, treat, try, ventilate, weed out, weigh, winnow



V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

SIFT
       Software Implemented Fault Tolerance (HIFT)


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

SIFT

   SHARE Internal Fortran Translator.  Translation utility
   designed for converting Fortran II to Fortran IV.  The word
   "sift" was often used as a verb to describe converting code
   from one language to another.  Sammet 1969, p.153.