A colony of breeding birds or other animals. / (by extension) A crowded tenement. / (Britain, historical) A place where criminals congregate, often an area of a town or city.

The area inside a recording studio designed to facilitate the mixing of audio for studio recordings. / A room serving as the centre of monitoring a building, controlling an operation etc.

(computing) Alternative spelling of rootkit

(literally, of a plant) Having deep roots; (of a non-living object) deeply and firmly embedded (in the ground, etc.). / (figuratively) Firmly established in thought or behaviour and difficult to change.

(surfing slang) The inside of a tube (i.e. of a wave making a tube).

Room or space in which to move or maneuver. / (figuratively) Freedom or leeway.

The portion of the deck raised to give increased headroom in the cabin. / The entire structure, including coamings.

A craftsman who lays, or repairs roofs. / A daredevil who performs stunts on tops of skyscrapers.

(physics) The root mean square of the velocities of all the molecules in a volume of gas; directly proportional to its temperature in the case of an ideal gas.

(mathematics, of a set of numbers or values) The square root of the arithmetic mean of the squares.