Groups of applied-for strings that are either identical or similar are called contention sets. More information is available in the New gTLD Program Applicant Guidebook.
The New gTLD Program processes leading up to and including, where applicable, an ICANN New gTLD Auction (including any CPE that may occur prior to, and which could eliminate the need for, an ICANN New gTLD Auction) provide the only permissible path to contention resolution. Any other resolution methods, such as private auctions or joint ventures, or any other arrangement designed to resolve contention privately, are strictly prohibited.