outrigger

tasapainottaja puhekieltä Any of various projecting beams or spars that provide support for a sailing ship's mast.
puhekieltä A long thin timber, pontoon, or other float attached parallel to a canoe or boat by projecting struts as a means of preventing tipping or capsizing.
puhekieltä An outrigger canoe or boat.
puhekieltä An iron bracket or brace for an oarlock projecting from the side of a rowing boat.
An extension mechanism, often retractable when not in use, on a boat, vehicle, or structure which helps to stabilize it to keep it from tip over|tipping over.
1938, w:Xavier Herbert|Xavier Herbert, w:Capricornia (novel)|Capricornia, New York: D. Appleton-Century, 1943, Chapter XII, p. 200, https://archive.org/details/capricornianovel00herb

From the cowcatcher hung the outrigger of the tricycle, leaping about as though in the grip of death itself, beating against the iron that had shattered it, striking the road, sending the gravel flying.