This is the 342nd most frequent Italian word.
hai
"Have" (second person singular present tense of "avere").
In this sentence, 'hai' is the second-person singular present tense of the verb 'avere', indicating possession.
Hai un libro interessante.
You have an interesting book.
Here, 'hai' functions as part of the idiomatic expression 'avere fame', which translates to 'to be hungry' in English, using possession to express a state of being.
Hai fame?
Are you hungry?
In this question, 'hai' is used as the auxiliary verb in the present perfect tense, combined with 'visitato', the past participle of the main verb, for forming the compound tense.