1. [n]  the momentary present; "Now is a good time to do it"; "it worked up to right now"
2. [adv]  in these times; "it is solely by their language that the upper classes nowadays are distinguished"- Nancy Mitford; "we now rarely see horse-drawn vehicles on city streets"; "today almost every home has television"
3. [adv]  without delay; with no time intervening; "he answered immediately"; "found an answer straightaway"; "an official accused of dishonesty should be suspended forthwith"; "Come here now!"
4. [adv]  used to preface a command or reproof or request; "now hear this!"; "now pay attention"
5. [adv]  at the present moment; "goods now on sale"; "the now-aging dictator"; "they are now abroad"; "he is busy at present writing a new novel"; "it could happen any time now"
6. [adv]  in the historical present; at this point in the narration of a series of past events; "President Kennedy now calls in the National Guard"; "Washington now decides to cross the Delaware"; "the ship is now listing to port"
7. [adv]  in the immediate past; "told me just now"
8. [adv]  (prefatory or transitional) "Now the next problem is..."

Now
Now

more details ...

1. \Now\, adv. [OE. nou, nu, AS. n[=u], nu; akin to D., OS., &
   OHG. nu, G. nu, nun, Icel., n[=u], Dan., Sw., & Goth. nu, L.
   nunc, Gr. ?, ?, Skr. nu, n[=u]. [root]193. Cf. {New}.]
   1. At the present time; at this moment; at the time of
      speaking; instantly; as, I will write now.
            I have a patient now living, at an advanced age, who
            discharged blood from his lungs thirty years ago.
                                                  --Arbuthnot.
   2. Very lately; not long ago.
            They that but now, for honor and for plate, Made the
            sea blush with blood, resign their hate. --Waller.
   3. At a time contemporaneous with something spoken of or
      contemplated; at a particular time referred to.
            The ship was now in the midst of the sea. --Matt.
                                                  xiv. 24.
   4. In present circumstances; things being as they are; --
      hence, used as a connective particle, to introduce an
      inference or an explanation.
            How shall any man distinguish now betwixt a parasite
            and a man of honor ?                  --L'Estrange.
            Why should he live, now nature bankrupt is ? --Shak.
            Then cried they all again, saying, Not this man, but
            Barabbas. Now, Barabbas was a robber. --John xviii.
                                                  40.
            The other great and undoing mischief which befalls
            men is, by their being misrepresented. Now, by
            calling evil good, a man is misrepresented to others
            in the way of slander.                --South.
   {Now and again}, now and then; occasionally.
   {Now and now}, again and again; repeatedly. [Obs.] --Chaucer.
   {Now and then}, at one time and another; indefinitely;
      occasionally; not often; at intervals. ``A mead here,
      there a heath, and now and then a wood.'' --Drayton.
   {Now now}, at this very instant; precisely now. [Obs.] ``Why,
      even now now, at holding up of this finger, and before the
      turning down of this.'' --J. Webster (1607).
   {Now . . . now}, alternately; at one time . . . at another
      time. ``Now high, now low, now master up, now miss.''
      --Pope.
   

2. \Now\, a.
   Existing at the present time; present. [R.] ``Our now
   happiness.'' --Glanvill.
   

3. \Now\, n.
   The present time or moment; the present.
         Nothing is there to come, and nothing past; But an
         eternal now does ever last.              --Cowley.