Webster’s Revised Unabridged Dictionary · 1913
Con
Con, adv. [Abbrev. from L. contra against.] Against the affirmative side; in opposition; on the negative side; — The antithesis of pro, and usually in connection with it. See Pro.
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.]
Of muses, Hobbinol, I con no skill. Spenser.
They say they con to heaven the highway. Spenser.
2. To study in order to know; to peruse; to learn; to commit to memory; to regard studiously.
Fixedly did look Upon the muddy waters which he conned As if he had been reading in a book. Wordsworth.
I did not come into Parliament to con my lesson. Burke.
To con answer, to be able to answer. [Obs.] — To con thanks, to thank; to acknowledge obligation. [Obs.] Shak.
Con, v. t. [See Cond.] (Naut.) To conduct, or superintend the steering of (a vessel); to watch the course of (a vessel) and direct the helmsman how to steer.