Poetry - Literature in metrical form. This is how poetry is defined (in a dictionary).
Such a description could only have been coined by a human being so utterly devoid of emotion and so terribly vain as to take on the task of defining 'poetry' in four words.
In saying all that, I personally prefer poetry that rhymes. Rhyme, rhythm and metre are more the tools of poetry rather than the defining quality.
I read/heard/recalled a few lines of a shayirii (couplet).

Khud ko kar bhuland itna
ki har taqdeer se pehle
khuda bande se khud pooche
ki 'bata teri razah kya hai'

Loosely translated, this means

Raise yourself to such great heights
that God himself, before he pens your destiny,
asks you 'tell me mortal, what is your wish'.

Now this is profound! In four lines this shayar (poet) has managed to describe an impossibility (not just because God himself is a debated concept!). What amazes me is the sheer magnitude of thought. When I am sitting at my desk eating lunch in front of the computer, thinking about how all that awaits me for the next 6 hours is endless darkness and scans of one kind or another, I question 'destiny' too. I also thank destiny when good things happen, but that for another day. So amidst all this questioning it never occurs to me that maybe, just maybe I could rise above it all and think 'darn it! I'll do these scans and not question anyone or anything because these scans will not define my whole life, I will'. Lo and Behold! one tiny thought for Amrita and a giant leap over destiny!