from
The Collaborative International Dictionary of English v.0.48
Tympan \Tym"pan\, n. [F., fr. L. tympanum a kettledrum, a panel
of a door. See {Tympanum}, and cf. {Tymp}.]
1. A drum. [Obs.]
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2. (Arch.) A panel; a tympanum.
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3. (Print.) A frame covered with parchment or cloth, on which
the blank sheets are put, in order to be laid on the form
to be impressed.
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{Tympan sheet} (Print.), a sheet of paper of the same size as
that to be printed, pasted on the tympan, and serving as a
guide in laying the sheets evenly for printing. --W.
Savage.
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