This is the 7233rd most frequent Polish word.
jesteście
"You are" (plural).
The word 'jesteście' is the second-person plural form of 'to be', used here to address multiple individuals as friends.
Jesteście moimi przyjaciółmi.
You are my friends.
'Jesteście' is used here to inquire collectively about the readiness of more than one person for the trip.
Czy jesteście gotowi na podróż?
Are you ready for the trip?
Here, 'jesteście' emphasizes the inclusion of all individuals being addressed collectively.