From The Collaborative International Dictionary of English v.0.48:
Con \Con\, v. t. [imp. & p. p. Conned; p. pr. & vb. n.
Conning.] [AS. cunnan to know, be able, and (derived from
this) cunnian to try, test. See Can, v. t. & i.]
1. To know; to understand; to acknowledge. [Obs.]
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Of muses, Hobbinol, I con no skill. --Spenser.
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They say they con to heaven the highway. --Spenser.
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2. To study in order to know; to peruse; to learn; to commit
to memory; to regard studiously.
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Fixedly did look
Upon the muddy waters which he conned
As if he had been reading in a book. --Wordsworth.
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I did not come into Parliament to con my lesson.
--Burke.
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To con answer, to be able to answer. [Obs.]
To con thanks, to thank; to acknowledge obligation. [Obs.]
--Shak.
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