needle-nozle

from The Century Dictionary.

• noun In hydraulic impulse-turbines or jet-wheels, a form of long, slender, conical nozle for directing the jet of water against the buckets of the wheel, in which the velocity of water through the nozle is regulated, without disturbing the form or direction of the jet, by the axial motion of a corresponding long, slender, conical valve, called a needle-valve. See needle-valve.