sub·sist 
(səb-sĭst)
(səb-sĭst)v. sub·sist·ed, sub·sist·ing, sub·sists
v.intr.
1.
a. To exist; be.
b. To remain or continue in existence.
2. To maintain life; live: subsisted on one meal a day.
3. To be logically conceivable.
v.tr.
To maintain or support with provisions.
[Latin subsistere, to support : sub-, sub- + sistere, to stand; see stā- in the Appendix of Indo-European roots.]
sub·sister n.