The Sethen-class was a type of starship used by the Romulan Star Empire's Star Navy in the 24th century. The Sethen-class was a cargo transport design. (Last Unicorn RPG - The Way of Dera module: The Romulans)

This class presumably included a prototype ship that would be named Sethen, although no such ship was mentioned.

Romulan starship classes
Romulan language names	Alocala • Amarcan • Amosarr • Aye Mosaram • Baydron • Caladan • Comilius • D'delitham • D'deridex • D'dredar • Delitham • Delon Vastam • Deresus • D'gerok • D'Kazanak • Draconarius • D'renet • D'retex • D'ridren • D'sera • D'seren • D'tavan • D'theros • D'valek • D'vanga • D'viret • D'virin • D'Vorix • Galan Stelri • Ganum • Golgaroth • Graffler • Hathos • Horos • Ivarix • Kelkarrum • Klivai Vang'radai-class • Lanora • Llaiir'Dhael • Mandukam • Meret • Mogai ~ Norexan • Moorabbin • Morlasam Cl'vangas • Morlasasi Stelam • Mularr • Narvasam'al • Narvasam Stelas • Nei'hrr • Nelvek • Nir'at • N'renix • Ocala Sindari • Phaeros • Praex • Prelar • Ralaaram Ocala • Ralek • Ranajmar • Ras Lovah • R'daran • R'derex • Re'ravsam • Reemea • Revastal • R'tan • Serex • Sethen • Shirekral • Stelai'deletham • S'ten Vastam • S'ten Talasam • Takaan • Takara Morlatta • Talas Mosarum • Temar Vastaram • Temar Vastari • Thalan • Theron • Tirethi • T'kairin • T'kassan • T'korex • T'Liss • T'rasus • T'varo • Ustalam Stelas • Vadak • Vadaso Stelri • Vas Hatham • Vas Hatham (scout) • Vas'deletham • Vas'kalabam • Vas'maklaram • Vas'rosvlai • Vastagor Lattam • Vastagor Vastarum • Vastam Cl'vangas • Vastari Sanalam • Vasteme • Veles • Venator • Ventarix • Veranal • Vercaal • Verelan Vastarum • Vereleus • Vespin • Vidian • Vithrel • V'geren • V'gurin • V'tana • V'tir
Translated names	(Akif) • Battlehawk • "Bird of Paradise" • Bird of Prey • Bird of Prey (scout) • Centurion • Bright One • Comet of Destruction • Death Talon • Death Flyer • Defender of Stars • Enhanced Fire • Executioner • Explosive Avenger • Falcon • Free Flight • Fire Swarm • Gallant Carrier • Gallant Wing • Graceful Flyer • Great Defender • Griffin • Gryphon • Harpy • Hawk • Heavy Defender • Hunter • Imperial Hawk • Imperium • (Kalath) • Kestrel • (K'hanakh) • (K't'inga) • Legion • Little Nest • Nestar • Night Flyer • Nightwing • Nova • Phoenix • Praetor • Praetorian • Protector • Raptor • Scimitar • Senator • Shadow • Shrieking Bird • Shrike • Silver Bird • Skyfire • Snipe • Star Seeker • Starglider • Starlifter • Stormbird • Swarm • Swift Wing • Talon ~ Theta • Traitorous Enemy • Unbound Brother • Vengeance • Vigilant One • War Eagle • Whitewind ~ Whitewing • Wind Carrier • Wing of Doom • Wing of Vengeance • Winged Defender • Wings of Justice
Alphanumeric names	B-type warbird • CS2 • (D7 • D7 Akif • D7M) • E5 • F2 • H4 • H5 • I4 • I7 • J2 • J3 • J4 • J8 • (K3) • M4 • M8 • N1 • N2 • N5 • N8 • P2 • P3 • P12 • Q1 • Q4 • R1 • R4 • S3 • S4 • S9 • S11 • T2 • T5 • T10 • Theta • U4 • U7 • U9 • U13 • U15 • U21 • V1 • V2 • V4 • V5 • V6 • V7 • V8 • V9 • V11 (D7) • V20 • V27 • V30 ~ V31 • Z1
By time period or type	22nd century bird-of-prey • 2150s bird-of-prey • 23rd century bird-of-prey • late 23rd century bird-of-prey • 2370s bird-of-prey • attack raptor • cargo ship • colony ship • construction ship • mining freighter • repair ship • science vessel