turn tail

to run away in fear (and run is often added although this essentially makes it redundant)

Don't turn tail when you have a huge turnout like that.

by The Rerturn of Light Joker November 2, 2008

turning tail

Leaving due to cowardice.

Picture a mongrel putting its tail between its legs and peeing all over it and yelping, ki-yi, ki-yi, ki-yi off into the distance.

by Downstrike May 27, 2004