1. To support or maintain, esp. over a long period (enough oxygen to sustain life).
2. To nourish and encourage; lend strength to (she helped sustain the criminal enterprise).
3. To undergo; suffer (Charles sustained third-degree burns).
4. (Of a court) to uphold or rule in favor of (objection sustained).
5. To substantiate or corroborate (several witnesses sustained Ms. Sipes’s allegation).
6. To persist in making (an effort) over a long period (he sustained his vow of silence for the last 16 years of his life). ¡ª sustainment, sustentation, n. ¡ª sustainable, adj.