What is a ferret?

<a href="https://history.fnal.gov/felicia.html">"What is a ferret?"</a> was a Jeopardy! question on Jan. 9, during the Greatest of All Time tournament. Note that there is only one Fermilab. everyday objects Photo: Bo Hammer

“What is a ferret?” was a Jeopardy! question on Jan. 9, during the Greatest of All Time tournament. Note that there is only one Fermilab. Photo: Bo Hammer