now in WordNet English dictionary

1. without delay or hesitation; with no time intervening
   "he answered immediately"; "found an answer straightaway"; "an official accused of dishonesty should be suspended forthwith"; "Come here now!"
   immediately  instantly  straightaway  straight off  directly  now  right away  at once  forthwith  like a shot  immediately  instantly  straightaway  straight off  directly  now  right away  at once  forthwith  like a shot 
   
2. 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"
   now  at present  now  at present 
   
3. 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"
   nowadays  now  today  nowadays  now  today 
   
4. used to preface a command or reproof or request
   "now hear this!"; "now pay attention"
   now  now 
   
5. 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"
   now  now 
   
6. in the immediate past
   "told me just now"
   now  now 
   
7. (prefatory or transitional) indicates a change of subject or activity
   "Now the next problem is..."
   now  now 
   

1. the momentary present
   "Now is a good time to do it"; "it worked up to right now"
   now