adv.
Pronunciation: ˌ s ō s-t ə - ' nü-( ˌ )t ō , ˌ so ̇ s-
Function: adjective or adverb
Etymology: Italian, from past participle of sostenere to sustain, from Latin sustin ē re
Date: circa 1724
: sustained to or beyond the note's full value ― used as a direction in music