tube
/ˈtuːb/ /Brit ˈtjuːb/
noun
plural tubes
[count] a long, hollow object that is used especially to control the flow of a liquid or gas
an object shaped like a pipe
[count] :a soft, long, narrow container that has a small opening at one end and that contains a soft material which can be pushed out by squeezing
[count] :a thin, long, hollow part within an animal or plant
the tube US informal :the television
[noncount] Brit :the system of trains that run underground in London
go down the tubes
informal
to fail or become ruined
to be wasted or lost