THREE-SIDED
Three"-sid`ed, a.

Defn: Having three sides, especially three plane sides; as, a three- sided stem, leaf, petiole, peduncle, scape, or pericarp.

THREE-SQUARE
Three"-square`, a.

Defn: Having a cross section in the form of an equilateral triangle; — said especially of a kind of file.

THREE-TORQUE SYSTEM OF CONTROL
Three"-torque` system of control. (Aëronautics)

Defn: Any system of rudders by which the pilot can exert a turning moment about each of the three rectangular axes of an aëroplane or airship.

THREE-VALVED
Three"-valved`, a.

Defn: Consisting of, or having, three valves; opening with three valves; as, a three-valved pericarp.

THREE-WAY
Three"-way`, a.

Defn: Connected with, or serving to connect, three channels or pipes; as, a three-way cock or valve.