The word doka refers to 'songs of the way' or living poetic teaching. Aikidoists are also often refered to as Aikidoka. O'Sensei was such a language player, and in that vein I have come to use the word 'doka' to refer to ourselves as the 'living songs of the way.' It is an accurate, albeit, poetic interpretation. I feel like a vibrational song of this great path whenever i practice or reflect on my path. It is an amazingly powerful sensation. So, there's my definition.
Thanks for the clarification.