| Acronym | Definition |
|---|
| ZTO➣Zeta Tau Omega (sorority; est. 1999) |
| ZTO➣Zinc Tin Oxide |
| ZTO➣Zentrum fur Technische Orthopadie (German: Center for Technical Orthopedics) |
| ZTO➣Zaklad Techniki Odpylania (Polish: Department of Dust Removal Technology) |
| ZTO➣Zero Time Outage |
| ZTO➣Zambezi Times Online (news website; Zambia) |
| ZTO➣Zone Transportation Office |
| ZTO➣Zoom Theory Optimal (poker) |
| ZTO➣Zone Transportation Officer |