errand

n. short trip to accomplish a task; task, business which needs to be accomplished

(n.)
A special business intrusted to a messenger; something to be told or done by one sent somewhere for the purpose; often, a verbal message; a commission; as, the servant was sent on an errand; to do an errand. Also, one's purpose in going anywhere.
  

Noun
1. a short trip that is taken in the performance of a necessary task or mission
(hypernym) trip

      darner