Definition of "specialised"

Second, a railway research department represents a qualified and specialised consultancy service, to provide the basis for well-informed high-level decisions regarding new designs or possible lines of development. [...] Finally, a research department is desirable to carry out the more specialised trials and testing of manufacturers' equipment prior to its acceptance by the operating personnel.

1961 February, R. K. Evans, “The role of research on British Railways”, in Trains Illustrated, page 92

"Railways have to bear the very high fixed costs associated with the provision and maintenance of a specialised route system for their own exclusive use. [...]"

1962 December, “Dr. Beeching previews the plan for British Railways”, in Modern Railways, page 376

Specialised long-reach excavators with a clamshell grab then reach though the openings to lift the spoil to the surface, which is then deposited in articulated dump trucks (ADTs).

2023 March 8, Chris Howe, “Building the platform for Old Oak Common's platforms”, in RAIL, number 978, page 60