[1] : The Collaborative International Dictionary of English v.0.48

subsist \subsist"\, v. t.
   to support with provisions; to feed; to maintain; as, to
   subsist one's family.
   1913 webster

         he laid waste the adjacent country in order to render
         it more difficult for the enemy to subsist their army.
                                                  --robertson.
   1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

subsist \subsist"\, v. i. imp.  p. p. subsisted; p. pr. 
   vb. n. subsisting. l. subsistere to stand still, stay,
   remain alive; sub under + sistere to stand, to cause to
   stand, from stare to stand: cf. f. subsister. see stand.
   1. to be; to have existence; to inhere.
      1913 webster

            and makes what happiness we justly call,
            subsist not in the good of one, but all. --pope.
      1913 webster

   2. to continue; to retain a certain state.
      1913 webster

            firm we subsist, yet possible to swerve. --milton.
      1913 webster

   3. to be maintained with food and clothing; to be supported;
      to live. --milton.
      1913 webster

            to subsist on other men's charity.    --atterbury.
      1913 webster
see also:
subsisted subsisting stand 

[3] : WordNet (r) 2.0

subsist
     v : support oneself; "he could barely exist on such a low wage";
         "can you live on $2000 a month in new york city?"; "many
         people in the world have to subsist on $1 a day" syn: exist,
          survive, live
see also:
exist survive live 

[4] : Moby Thesaurus II by Grady Ward, 1.0

73 moby thesaurus words for "subsist":
   abide, be, be alive, be animate, be extant, be found,
   be in existence, be left, be met with, be present, be the case,
   be there, bide, breathe, carry on, continue, continue to be, cope,
   defeat time, defy time, draw breath, dwell, eke out, endure, exist,
   extend, fetch breath, get by, go on, happen to be, have being,
   have life, have place, hold, hold on, hold out, keep, keep afloat,
   keep on, last, last long, last out, live, live and breathe,
   live on, live through, maintain, make ends meet, make out, manage,
   move, obtain, occur, perdure, perennate, persist, prevail, remain,
   respire, rest, run, run on, scrape along, stand, stay, stay on,
   survive, sustain, tarry, tide over, walk the earth, wear,
   wear well

Subsist >> S Words
Subsist, definition of term: Subsist
subsist_pag1.html