I really like the word "sadhana" to describe a yoga class. It is a term for "a means of accomplishing something" or more specifically "spiritual practice." Sādhana is a discipline undertaken in the pursuit of a goal. Abhyāsa is repeated practice performed with devotion, observation and reflection. Kriyā, or action, also implies perfect execution with study and investigation. Therefore, sādhana, abhyāsa, and kriyā all mean one and the same thing. A sādhaka, or practitioner, is one who skillfully applies...mind and intelligence in practice towards a spiritual goal.
My teacher, Shiva Rea describes sadhana as, a groove to one's self, and I like this defination. The idea of combining practice, skill, and action with intelligence as a devotional act really appeals to me. Perfection is not the goal, but the act of refining through dedication and practice. Its like a jewlery maker that leans over her art for hours upon hours a day to produce something beautiful that will be given away. To me, this is the essence of a yoga practice; a continual refinement; an act of devotion.