English definition of “top sth up”
top sth up — Phrasal Verb with top
/tɒp/ verb [T] (present participle topping, past tense and past participle topped)
UK (US top sth off)
› to add more liquid to a container in order to make it full
› to add more of something, especially money, to an existing amount to create the total you need: Can I top up my mobile phone here?