what is a empty threat?

[mcbryanjeff86]

I work for an airline company and went out for a de-icing course and i ran into one of the company's pilots, he heard i got training to de-ice
planes if needed in the winter, and he says we look forward to you de icing and i said yeah thats if i am still there, and says to me don't give any empty threats yes you will be, we miss you?

 

[lajoy05]

An empty threat is a threat made that isnt carried through.