n (colloquial) Often in plural ('rännit'), a system for collecting the rainwater from the roof and leading it down to a drain or to the ground.
n (colloquial) Any of the main components of such system, particularly a downspout (syöksytorvi) or a gutter (sadevesikouru).
n A trough which is open in one or both ends, especially when used as component in a liquid handling system.
n (context|mining) A launder (trough used by miners to separate metal-rich pieces from the crushed ore by washing)