Definition of "sostenuto" [‖Sos•te•nu•to]

• In a manner that is sustained as long as or beyond a note's full value. Used chiefly as a direction. (adverb)
• A sostenuto passage or movement. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "It also refers to marriage as a "wild sostenuto of the heart," a phrase I use as an anchor point in romantic conversations with my wife."
• "There are only a few sound characteristics that a pianist can control: hammer and damper timing, individual note velocities the force with which each note is struck, and the pedal controls, una corda, sostenuto and damper."
• "The piano is propably among the easiest instruments to apply this kind of processing to, but even here there are problems with techniques such as half-pedalling, use of sostenuto pedal, etc."