Definition of tank noun from the Oxford Advanced Learner's Dictionary

Oxford3000

tank

noun
tæŋk
 
; tæŋk
 
 
1 a large container for holding liquid or gasa hot water tanka fuel tanka fish tank (= for keeping fish in) see also septic tank, think tank2 (also tankful
tæŋkfʊl
 
; tæŋkfʊl
 
)
the contents of a tank or the amount it will holdWe drove there and back on one tank of petrol.
3 a military vehicle covered with strong metal and armed with guns. It can travel over very rough ground using wheels that move inside metal belts.4 (Indian English) an artificial pool, lake or reservoir