They’re phrases we hear all the time.  We know what they mean, but most people probably don’t know where they began.

At least two of them come from the boxing ring.  To throw in the towel means to give up.  Originally it was to throw in the sponge.  A trainer uses a sponge to wipe down his fighter between rounds.  If the trainer saw his fighter was clearly beaten, he would throw in the sponge to signify they were done.  Later it became a towel thrown in the ring.

 Hang in there is also from the ring.  It’s when a boxer would hold on to the ropes or force an opponent into the ropes until the end of the round or the end of the bout, refusing to give up.

Skid row is a part of town you usually don’t want to be in.  It comes from a section of Seattle, Washington in the 1800’s where logs headed to saw mills would be skidded from where they were cut in the forest.  Living along this skid road were lumberjacks, prostitutes and panhandlers.  A pretty seamy place to be in.  Skid road later became known as Skid Row.

To show your true colors – a nautical term.  Enemy ships, sometimes pirate ships would display the flag of a friendly nation to get close to an unsuspecting target.  At the last minute they’d hoist their real flag and show their true colors.

Second string – often used to describe a replacement or back-up player on a sports team.  In medieval times, it was always a good idea to carry an extra string in case the one on your bow broke.  It was your second string. 

Long in the tooth – means getting old.  As horses age, their gums recede and it looks like their teeth are getting longer.  The longer their teeth look, the older they are.