This form was introduced to AllPoetry and promoted by Jeff Green, aka Crickenjeff.
I find references to the fifteener as being a very old poetic form, but with no specifications as to meter or rhyme. Jeff's form requires lyrical meter and couplet rhyme. You may choose any meter and rhyme pattern.
The meter of a fine tertius fifteener is like this:
diddy-DUM-di diddy-DUM-di diddy-DUM-di diddy-DUM
It is quite addictive meter, much more complex than the rest
With it's triple tertius paeons followed by an anapest.
Play? Bawl? (Fifteener)
The most talented of poets had all gathered at the meet,
they had traveled from afar on this occasion to compete.
When the master from olde England asked for anapestic verse,
or for tertius combinations, which I figured would be worse,
like a quakin' asp I shivered for just iambs give me pause.
Though my mentor's shoulders shrugged, "You won't be breaking any laws
but the caliber of poet, especially at the top
all deserved their invitation, you won't want to pen a flop."
With that ringing non-endorsement I was tempted then to pass,
when I thought of all the heroes who had struggled to the last;
While the wisps of nighttime zephyrs then pushed random thought a way,
I remembered all the champions who down, still chose to play.
It was time for this young poet to show all that he was stout.
'Cus the ball game isn't over until Casey's bat strikes out.
© Lawrencealot - September 23, 2013
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