Miles O'Brien (Star Trek)

Miles Edward O'Brien is a character in the Star Trek franchise, portrayed by actor Colm Meaney. O'Brien was originally the head transporter operator for the USS Enterprise-D, with a recurring role in all seven seasons of Star Trek: The Next Generation. Promoted to chief of operations for Deep Space Nine, O'Brien became a principal character on the series of the same name. Portrayed in 225 episodes overall, O'Brien is the Star Trek character with the second most appearances in the franchise (exceeded only by Worf, portrayed by Michael Dorn).

O'Brien is the only major Star Trek character described as both ethnically Irish and born in Ireland; Colm Meaney, the actor who portrays him, is Irish. He is also the only regular Star Trek character to be a non-commissioned officer.