What is a jellyfish galaxy? – Extreme Speed Zone

Question: What is a jellyfish galaxy?
- Keywords:
  fish,
  galaxy,
  jellyfish
Asked by ashtm001 to Sam on 24 Jun 2013.
- Sam Geen answered on 24 Jun 2013:
  
  It’s a galaxy whose gas is being ripped out as it passes through the hot, low-density gas inside a galaxy cluster:
  
  The streams of gas being pulled out make it look a little bit like a jellyfish.

Question: What is a jellyfish galaxy?