Roebuck (Irish: Reabóg), also originally known as "Rabuck", is a townland and the name of a former estate in the baronies of Dublin and Rathdown in Ireland.

The townland incorporates roughly all the land in the triangle between Clonskeagh, Dundrum and Mount Merrion. Historically significant buildings which exist (or existed) in the area include Mountainville House, Mount Anville, St. Thomas's Church, Moorfield, Mount Dillon, Castleview, Owenstown House, Roebuck Hill, Hermitage House, Friarsland House, Prospect Hall, Roebuck Lodge, Bellefield, Roebuck Park, Belfield House and Harlech House.

Roebuck became established as a location shortly after the Norman invasion of Ireland (from 1169). In the 13th century, the area was owned by Fromund Le Brun, the Lord Chancellor of Ireland.

In 1261, the area around Roebuck was owned by Fromund Le Brun, the Lord Chancellor of Ireland, and a castle was built there in the 13th century. In 1466, his descendant Elizabeth le Brun married Robert Barnewall, 1st Baron Trimlestown.

In 1509, the 3rd Baron Trimlestown who was later to become Lord Chancellor of Ireland, is recorded as living at the castle.

The origins of the modern castle are said to have been in the building of a castle by Robert Barnewall, 5th Baron Trimlestown sometime in the 16th century.

The castle was badly damaged in the Irish Rebellion of 1641.

The Civil Survey of 1654-56 noted that the lands of 'Rabuck' extended to 500 acres.