bobsled       
noun US uk/ˈbɒb.sled/ us/ˈbɑːb.sled/ (UK bobsleigh, /ˈbɒb.sleɪ/ /ˈbɑːb.sleɪ/)
 [ C ]大雪橇 
a small vehicle with long metal blades under it, built for racing down tracks covered with ice
  Occasionally the bobsleds crash and turn over.
 He rode in a bobsled for the first time yesterday.
 - More examples
 - Bobsleds are now built to have the best possible aerodynamics with lightweight construction and alloy runners.
 - The United States won the four-man bobsled.
 - On the bobsled tracks, carving hundredths of a second from a team's runs can make the difference between a gold medal and also-ran status.
 
Synonym: bob