#1 run down v. trace; "We are running down a few tips". wn #2 run down v. move downward; "The water ran down". wn #3 run down v. injure or kill by running over, as with a vehicle. wn #4 run down v. use up all one's strength and energy and stop working; "At the end of the march, I pooped out". wn #5 run down v. examine hastily; "She scanned the newspaper headlines while waiting for the taxi". wn