"Yeah, I guess it slipped my mind because the name is so stupid."
The trynar shield was a powerful deflector shield that surrounded the Detrion system, erected by Nick Locarno in 2381 to defend his newly formed Nova Fleet. The shield functioned in both directions, preventing exit as well as entry. It was so named because it was operated by a trio of Bynars on Nova One.
Locarno assured his followers that the trynar shield was indestructible, though he was aware that it could be penetrated by sufficient firepower or a large enough force. Indeed, the USS Cerritos was able to breach the barrier by setting the derelict Orion destroyer Retribution to collide with the shield, creating an opening long enough for the Cerritos captain's yacht to slip into the system. Locarno's followers, already having doubts due to his controlling and reckless behavior, abandoned him after the shield was breached. (LD: "Old Friends, New Planets")