noun one who, or that which, upholds or sustains; a sustainer.
2. sustain ·vt to aid, comfort, or relieve; to vindicate.
3. sustain ·vt hence, to keep from sinking, as in despondence, or the like; to support.
4. sustain ·vt to suffer; to bear; to undergo.
5. sustain ·vt to endure without failing or yielding; to bear up under; as, to sustain defeat and disappointment.
6. sustain ·vt to prove; to establish by evidence; to corroborate or confirm; to be conclusive of; as, to sustain a charge, an accusation, or a proposition.
7. sustain ·vt to allow the prosecution of; to admit as valid; to sanction; to continue; not to dismiss or abate; as, the court sustained the action or suit.
8. sustain ·vt to maintain; to keep alive; to support; to subsist; to nourish; as, provisions to sustain an army.
9. sustain ·vt to keep from falling; to bear; to uphold; to support; as, a foundation sustains the superstructure; a beast sustains a load; a rope sustains a weight.