Terry Ahern was a Starfleet officer during the late 24th century.
During the 2370s, Ahern was a member of the Research and Development team responsible for the construction of several Defiant-class starships, including the USS Defiant and USS Valiant at the Antares Ship Yards in 2370-71, and USS Sao Paulo at Utopia Planitia Ship Yards in 2375. (DS9: "The Die is Cast", dedication plaque; DS9: "Valiant", dedication plaque; DS9: "The Dogs of War", dedication plaque)
This character was only mentioned in writing.
Ahern was named for craft service associate Terry Ahern.