The Collaborative International Dictionary of English v.0.48:

Subsist \Sub*sist"\, 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.
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            And makes what happiness we justly call,
            Subsist not in the good of one, but all. --Pope.
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   2. To continue; to retain a certain state.
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            Firm we subsist, yet possible to swerve. --Milton.
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   3. To be maintained with food and clothing; to be supported;
      to live. --Milton.
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            To subsist on other men's charity.    --Atterbury.
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