Definition of "tunneller"

Approach roads have been formed, and a new town to house 500 persons, including the engineers, tunnellers, outside workers and their families is being built.

1950 August, “The Rimutaka Incline and Deviation, New Zealand”, in Railway Magazine, page 547

Entering the tunnel, we pass a small shrine above our heads which contains a statue of St Barbara, the patron saint of tunnellers. It is traditional to have such shrines on every tunnel site.

2022 March 23, Paul Bigland, “HS2 is just 'passing through'”, in RAIL, number 953, page 41