son·net (s?n??t)n.1. A 14-line verse form often in iambic pentameter, having one of several conventional rhyme schemes and usually featuring a shift in mood or tone after the eighth or twelfth line.2. A poem in this form.[French or Italian sonetto (French, from Italian), from Old Provençal sonet, diminutive of son, song, from Latin sonus, a sound; see swen- in Indo-European roots.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.sonnet (?s?n?t) prosodyn (Poetry) a verse form of Italian origin consisting of 14 lines in iambic pentameter with rhymes arranged according to a fixed scheme, usually divided either into octave and sestet or, in the English form, into three quatrains and a coupletvb1. (Poetry) (intr) to compose sonnets2. (Poetry) (tr) to celebrate in a sonnet[C16: via Italian from Old Provençal sonet a little poem, from son song, from Latin sonus a sound]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014son?net (?s?n ?t) n. a poem, properly expressive of a single idea or sentiment, of 14 lines, usu. in iambic pentameter, with rhymes arranged in a fixed scheme, being in the Italian form divided into a major group of eight lines followed by a minor group of six lines and in a common English form into three quatrains followed by a couplet. [1550?60;