Hypertext Webster Gateway: "duplicate"

From Webster's Revised Unabridged Dictionary (1913) (web1913)

I send a duplicate both of it and my last dispatch.
-- Sir W.
Temple.

2. (Law) An original instrument repeated; a document which is
the same as another in all essential particulars, and
differing from a mere copy in having all the validity of
an original. --Burrill.

From Webster's Revised Unabridged Dictionary (1913) (web1913)

2. To make a duplicate of (something); to make a copy or
transcript of. --Glanvill.

3. (Biol.) To divide into two by natural growth or
spontaneous action; as, infusoria duplicate themselves.

From Webster's Revised Unabridged Dictionary (1913) (web1913)

{Duplicate proportion} or {ratio} (Math.), the proportion or
ratio of squares. Thus, in geometrical proportion, the
first term to the third is said to be in a duplicate ratio
of the first to the second, or as its square is to the
square of the second. Thus, in 2, 4, 8, 16, the ratio of 2
to 8 is a duplicate of that of 2 to 4, or as the square of
2 is to the square of 4.

From WordNet (r) 1.7 (wn)

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