Let's take a few definitions of the word pattern to see what is typically thought of it:

1. The fifth definition from the World Book Dictionary gives us "the arrangement and use of content in particular forms, styles, etc., in a work of literature, music, etc."
2. Dictionary.com, "5a: Form and style in an artistic work or body of artistic works."
3. Perhaps the most interesting one for us is found in an unexpected place, the Merriam-Webster's Dictionary of Law, "a recognizably consistent series of related acts."

Each definition adds something valuable to our discussion. The first tells us that pattern is an arrangement of forms, and the use of the word "form" should not be overlooked since we are talking about the "formal," the structural (Apollonian), aspects of poetry here, after all.

The second reiterates the importance of form, but adds that, in this instance, it is the application of form in an "artistic work." The addition of "art" means that pattern is not accidental, but is performed by the artist (the poet, who, through practice, learns to contend with particular formal issues and applies them thereafter when the time is right).

The third definition adds something related to the second, which is that pattern is a series (especially the aural aspects, which are delivered in time, like music), and as a series there is either a predictable repetition, addition, or subtraction of a particular aspect. A pattern then may not only be a simple repetition, but can also be a predictable change within a series. As in math, where the series 2,4,6,8,10 is predictable but not simply repetitive, a pattern in poetry may take a similar form. We also get in this definition that a pattern is a series of related "acts," and those acts (as artistic acts performed by the poet) are again not accidental, but deliberative poetic actions that help convey the poem to the audience.

A sidenote would have to admit that with practice, the poet begins to perform these actions without the explicit thoughts that the beginner needs. This is comparable to a dancer who practices a step thousands of times so that when the time comes at the recital, her deliberate thoughts are no longer a burden and she can perform gracefully. The application of pattern at the right time in the writing process is something derived over years of practice and will continue to frustrate and intrigue any poet as long as he or she writes.

Because these three definitions are not speaking of poetic pattern specifically, we must also remember to add to our definition that poetic pattern is made of the aural and visual aspects of a poem. These are the two readily available material aspects of the poem (poets rarely seem concerned by, say, how a word physically smells, or, except in cases of Braille poetry, how it feels on the page).

So can we then offer our own definition of poetic pattern? Let's say that it is:

It is not such a stretch to say that the discussion of pattern and variation makes up a large chunk of the study and practice of poetics. To create a poem, some pattern and variation must be applied to the words. Something may be poetic without being a poem (a metaphor in a novel, for example,) but this is another matter. Things like metaphors come from a branch of poetics that deals with what are called tropes, and they are another matter from the discussion here. Here we're talking about poems specifically, not something "poetic," and what makes a poem a poem (and here we take a risk by defining such a thing...there will inevitably be discontents, but it must be done), is the presence of the material (aural and visual) aspects of words shaped into particular forms. Said another way, poem-making involves the rendering of the material aspects (aural, visual) of words into structures that are relevant to the meaning of those words. The establishment of pattern is the consistent application of particular material aspects across a given poem. But that is only half of the matter.

We must also deal with variation.