Source : Webster's Revised Unabridged Dictionary (1913)

Woe \Woe\, n. [OE. wo, wa, woo, AS. w[=a], interj.; akin to D.
   wee, OS. & OHG. w[=e], G. weh, Icel. vei, Dan. vee, Sw. ve,
   Goth. wai; cf. L. vae, Gr. ?. [root]128. Cf. {Wail}.]
   [Formerly written also {wo}.]
   1. Grief; sorrow; misery; heavy calamity.

            Thus saying, from her side the fatal key, Sad
            instrument of all our woe, she took.  --Milton.

            [They] weep each other's woe.         --Pope.

   2. A curse; a malediction.

            Can there be a woe or curse in all the stores of
            vengeance equal to the malignity of such a practice?
                                                  --South.

   Note: Woe is used in denunciation, and in exclamations of
         sorrow. `` Woe is me! for I am undone.'' --Isa. vi. 5.

               O! woe were us alive [i.e., in life]. --Chaucer.

               Woe unto him that striveth with his Maker! --Isa.
                                                  xlv. 9.

   {Woe worth}, Woe be to. See {Worth}, v. i.

            Woe worth the chase, woe worth the day, That costs
            thy life, my gallant gray!            --Sir W.
                                                  Scott.

Woe \Woe\, a.
   Woeful; sorrowful. [Obs.]

         His clerk was woe to do that deed.       --Robert of
                                                  Brunne.

         Woe was this knight and sorrowfully he sighed.
                                                  --Chaucer.

         And looking up he waxed wondrous woe.    --Spenser.

Source : WordNet®

woe
     n 1: misery resulting from affliction [syn: {suffering}]
     2: intense mournfulness [syn: {woefulness}]