Drive

According to the Dictionary Drive means..

# operate or control a vehicle; "drive a car or bus"; "Can you drive this four-wheel truck?"
# travel or be transported in a vehicle; "We drove to the university every morning"; "They motored to London for the theater"
# cause someone or something to move by driving; "She drove me to school every day"; "We drove the car to the garage"
# force: force into or from an action or state, either physically or metaphorically; "She rammed her mind into focus"; "He drives me mad"
# to compel or force or urge relentlessly or exert coercive pressure on, or motivate strongly; "She is driven by her passion"
# repel: cause to move back by force or influence; "repel the enemy"; "push back the urge to smoke"; "beat back the invaders"
# compel somebody to do something, often against his own will or judgment; "She finally drove him to change jobs"
# push, propel, or press with force; "Drive a nail into the wall"
# cause to move rapidly by striking or throwing with force; "drive the ball far out into the field"
# tug: strive and make an effort to reach a goal; "She tugged for years to make a decent living"; "We have to push a little to make the deadline!"; "She is driving away at her doctoral thesis"
# move into a desired direction of discourse; "What are you driving at?"
# the act of applying force to propel something; "after reaching the desired velocity the drive is cut off"
# have certain properties when driven; "This car rides smoothly"; "My new truck drives well"
# a mechanism by which force or power is transmitted in a machine; "a variable speed drive permitted operation through a range of speeds"
# work as a driver; "He drives a bread truck"; "She drives for the taxi company in Newark"

These definitions apply to the term "drive" in bluegrass music. To "propel", to "press with force" Yes, there is no certain speed that indicates that a song is "drivin." When you are in your car you are "driving" no matter if you are going 20 or 90, however when a jammin song comes on and your bobbing your head now that is "drivin."

To push with force almost like stretching the tempo and parameters of the song with becoming behind or too far in front of the song. To me when I hear a song and I immediately tap my foot and bob my head then that song has that drivin sound and not all songs have that; on that note not all songs should have it.