Webster's Revised Unabridged Dictionary · 1913

Con-

Con- ({not transcribed})

A prefix, from L. cum, signifying with, together, etc. See Com-.

Con , adverb

[Abbrev. from Latin 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 , transitive verb

[Anglo-Saxon 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. [Obsolete]
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
Collocations (2)
To con answer , to be able to answer. [Obsolete]
To con thanks , to thank; to acknowledge obligation. [Obsolete] — Shakespeare

Con , transitive verb

[See Cond.]

(Nautical) To conduct, or superintend the steering of (a vessel); to watch the course of (a vessel) and direct the helmsman how to steer.