It

It's the name resting forever
On the tip of your tongue
It's the time you struck out
Because you never swung

It's looking for the brightside
On the darkside of the moon
It's the tingling aftertaste
That evaporates to soon

It's the one you let get away
And the time you held on to long
It's all those words you meant to say
And the times that you were wrong

It's the reason for joy
It's the reason for strife
It's the undefinable "if"
In this thing we call "life"