Actually those aren't very good definitions at all! What questioning the oxford online dictionary dogma!!!!!!

The definitons are certainly not comprehensive. Everyone involved in traditional music uses these terms to describe tunes AND dances all of the time! (something the online dictionary include for Hornpipe but inexplicably not for Jig and Reel)

A reel may well be a dance but it's also a tune. And it is the definition of the tune that we are disputing here. At one time it may have been the tune for the dance but now they have a life of there own. These are the sessions that I am most often found in.

Don't just say "allright youngun, one day you'll understand" because you don't have an actual answer. That demonstrates your limited depth of knowledge on the subject.