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Webster 1913 Edition

Adj.

Consisting of two threads twisted together; using two threads.

(Mech.)

Having two screw threads instead of one; – said of a screw in which the pitch is equal to twice the distance between the centers of adjacent threads.

Adj.

Consisting of two threads twisted together.

double-threaded ‎(not comparable)

(engineering) Consisting of two threads twisted together; using two threads.
(engineering) Having two **** threads instead of one; said of a **** in which the pitch is equal to twice the distance between the centers of adjacent threads.