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

tank

verb
tæŋk
 
; tæŋk
 
 
1 [intransitive] (North American English) (of a company or a product) to fail completelyThe company's shares tanked on Wall Street.2 [transitive, intransitive] tank (something) (North American English, sport) to lose a game, especially deliberatelyShe was accused of tanking the match.
Phrasal verbs

tank (something) up

(North American English) to fill a car with petrol/gasHe tanked up and drove off.We stopped to tank the car up.