
1) Old Macintosh model
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https://www.crosswordclues.com/clue/quadra

square frame; plinth
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http://phrontistery.info/q.html

• (n.) The plinth, or lowest member, of any pedestal, podium, water table, or the like. • (n.) A fillet, or listel.
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http://thinkexist.com/dictionary/meaning/quadra/
Quad'ra noun ;
plural Quadræ . [ Latin , a square, the socle, a platband, a fillet.]
(Architecture) (a) The plinth, or lowest member, of any pedestal, podium, water table, or the like.
(b) A fillet, or listel.
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http://www.encyclo.co.uk/webster/Q/1

In architecture a quadra is the plinth, or lowest member, of any pedestal, podium, water table, or the like. The term is also used to describe the border around a bas-relief.
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http://www.probertencyclopaedia.com/browse/TQ.HTM

a small molding, as a fillet.
Found on
https://www.infoplease.com/dictionary/quadra
No exact match found.