three-port
three-position
three-primary
three-quarter
three-rate
three-roll
three-screws
three-section
three-sigma
three-sixty
  three-speed
three-star
three-step
three-storied
three-terminal
three-thread
three-tube
three-value
three-vessel
three-voltmeter
three-wattmeter

    three-speed power shift transmission

    трёхскоростная трансмиссия, переключаемая под нагрузкой