Definition of tube
1 : any of various usually cylindrical structures or devices: such as
a : a hollow elongated cylinder especially : one to convey fluids
b : a soft tubular container whose contents (such as toothpaste) can be removed by squeezing
c(1) : tunnel
d : the basically cylindrical section between the mouthpiece and bell that is the fundamental part of a wind instrument
2a : a slender channel (such as a fallopian tube or a pollen tube) within a plant or animal body : duct
b : the narrow basal portion of a corolla with united petals or a calyx with united sepals
3 : inner tube
5 : an article of clothing shaped like a tube
a tube top tube socks
down the tube or down the tubes
: into a state of collapse or deterioration
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Time Traveler for tube
The first known use of tube was in 1651
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