| Acronym | Definition |
|---|
| NTRA | National Thoroughbred Racing Association |
| NTRA | National Telecommunication Regulatory Authority (Egypt) |
| NTRA | National Training Reform Agenda |
| NTRA | Nano Technology Research Association (Korea) |
| NTRA | Norwegian Telecommunications Regulatory Authority |
| NTRA | National Touch Rugby Association (Australia) |
| NTRA | National Trail Racing Association |
| NTRA | National Team Roping Association |
| NTRA | North Trent Research Alliance (UK) |
| NTRA | National Towing & Recovery Association |
| NTRA | National Tenants & Residents Association |
| NTRA | National Tot Rod Association (UK) |
| NTRA | National TESD Research Agenda (Philippines) |
| NTRA | Nanaimo Therapeutic Riding Association |
| NTRA | National Tumor Registrars Association, Inc. |
| NTRA | North Texas Rehabilitation Association |
| NTRA | National Tyre Recycling Association (UK) |