a poem, properly expressive of a single, complete thought, idea, or sentiment, of 14 lines, usually in iambic pentameter, with rhymes arranged according to one of certain definite schemes, being in the strict or Italian form divided into a major group of 8 lines (the octave) followed by a minor group of 6 lines (the sestet), and in a common English form into 3 quatrains followed by a couplet.

Blue Sonnet anyone?

Sonnet XL - Snakespear

Like as the waves make towards the pebbled shore,

So do our minutes hasten to their end;
Each changing place with that which goes before,
In sequent toil all forwards do contend.
Nativity, once in the main of light,
Crawls to maturity, wherewith being crown'd,
Crooked eclipses 'gainst his glory fight,
And Time that gave doth now his gift confound.
Time doth transfix the flourish set on youth
And delves the parallels in beauty's brow,
Feeds on the rarities of nature's truth,
And nothing stands but for his scythe to mow:
And yet to times in hope, my verse shall stand
Praising thy worth, despite his cruel hand.