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English definition of “on”


preposition (FOOD/FUEL/DRUG)    /ɒn/ US  /ɑːn/
B2 used to show something that is used as food , fuel , or a drug : What do mice live on? Does this radio run on batteries ? Is he on drugs ?Drug addictionAddictionEatingBiting, chewing and swallowingFuelsPetroleum products especially when used as fuel Grammar:On, ontoOn and onto are prepositions.
(Definition of on preposition (FOOD/FUEL/DRUG) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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