The Collaborative International Dictionary of English v.0.48:

Soon \Soon\ (s[=oo]n), adv. [OE. sone, AS. s[=o]na; cf. OFries.
   s[=o]n, OS. s[=a]na, s[=a]no, OHG. s[=a]r, Goth. suns.]
   1. In a short time; shortly after any time specified or
      supposed; as, soon after sunrise. "Sooner said than done."
      --Old Proverb. "As soon as it might be." --Chaucer.
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            She finished, and the subtle fiend his lore
            Soon learned.                         --Milton.
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   2. Without the usual delay; before any time supposed; early.
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            How is it that ye are come so soon to-day? --Ex. ii.
                                                  18.
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   3. Promptly; quickly; easily.
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            Small lights are soon blown out, huge fires abide.
                                                  --Shak.
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   4. Readily; willingly; -- in this sense used with would, or
      some other word expressing will.
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            I would as soon see a river winding through woods or
            in meadows, as when it is tossed up in so many
            whimsical figures at Versailles.      --Addison.
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   As soon as, or So soon as, immediately at or after
      another event. "As soon as he came nigh unto the camp . .
      . he saw the calf, and the dancing." --Ex. xxxii. 19. See
      So . . . as, under So.

   Soon at, as soon as; or, as soon as the time referred to
      arrives. [Obs.] "I shall be sent for soon at night."
      --Shak.

   Sooner or later, at some uncertain time in the future; as,
      he will discover his mistake sooner or later.

   With the soonest, as soon as any; among the earliest; too
      soon. [Obs.] --Holland.
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