sustain

v. support, provide for, finance; support from below; nourish; assist; encourage, comfort; endure, withstand; prolong, maintain, preserve; experience, undergo; uphold, affirm; confirm

Sustain is a parameter of musical sound in time. As its name implies, it denotes the period of time during which the sound is sustained before it becomes inaudible. Furthermore, sustain is the third of the four segments in an ADSR envelope. The sustain portion of the ADSR envelope begins when the attack and decay portions have run their course, and continues until the key is released. The sustain control is used to determine the level at which the envelope will remain. While the attack, decay, and release controls are rate or time controls, the sustain control is a level control.
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Verb
1. lengthen or extend in duration or space; "We sustained the diplomatic negociations as long as possible"; "prolong the treatment of the patient"; "keep up the good work"
(synonym) prolong, keep up
(hypernym) continue, uphold, carry on, bear on, preserve
(hyponym) retain, continue, keep, keep on, keep going
(derivation) upholder, maintainer, sustainer
2. undergo (as of injuries and illnesses); "She suffered a fracture in the accident"; "He had an insulin shock after eating three candy bars"; "She got a bruise on her leg"; "He got his arm broken in the scuffle"
(synonym) suffer, have, get
(hypernym) experience, receive, have, get, undergo
(hyponym) break down, collapse
(verb-group) have
3. provide with nourishment; "We sustained ourselves on bread and water"; "This kind of food is not nourishing for young children"
(synonym) nourish, nurture
(hypernym) provide, supply, ply, cater
(hyponym) carry
(derivation) sustenance, sustentation, sustainment, maintenance, upkeep
4. supply with necessities and support; "She alone sustained her family"; "The money will sustain our good cause"; "There's little to earn and many to keep"
(synonym) keep, maintain
(hypernym) have, have got, hold
(hyponym) patronage
(derivation) support, keep, livelihood, living, bread and butter, sustenance
5. be the physical support of; carry the weight of; "The beam holds up the roof"; "He supported me with one hand while I balanced on the beam"; "What's holding that mirror?"
(synonym) hold, support, hold up
(hyponym) scaffold
6. admit as valid; "The court sustained the motion"
(hypernym) admit, acknowledge
7. establish or strengthen as with new evidence or facts; "his story confirmed my doubts"; "The evidence supports the defendant"
(synonym) confirm, corroborate, substantiate, support, affirm
(hyponym) back, back up

(v. t.)
To suffer; to bear; to undergo.
  

(v. t.)
To prove; to establish by evidence; to corroborate or confirm; to be conclusive of; as, to sustain a charge, an accusation, or a proposition.
  

(v. t.)
To maintain; to keep alive; to support; to subsist; to nourish; as, provisions to sustain an army.
  

(v. t.)
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.
  

(v. t.)
To endure without failing or yielding; to bear up under; as, to sustain defeat and disappointment.
  

(v. t.)
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.
  

(v. t.)
To aid, comfort, or relieve; to vindicate.
  

(v. t.)
Hence, to keep from sinking, as in despondence, or the like; to support.
  

(n.)
One who, or that which, upholds or sustains; a sustainer.
  

     issuant