now vs past

now

noun
  • The present time. 

  • The state of not paying attention to the future or the past. 

  • A particular instant in time, as perceived at that instant. 

adv
  • Used to indicate a context of urgency. 

  • Sometimes; occasionally. 

  • Used to address a switching side, or sharp change in attitude from before. (In this usage, now is usually emphasized). 

  • At the present time. 

  • Used to introduce a point, a qualification of what has previously been said, a remonstration or a rebuke. 

  • At the time reached within a narration. 

  • Differently from the immediate past; differently from a more remote past or a possible future; differently from all other times. 

intj
  • Indicates a signal to begin. 

adj
  • Fashionable; popular; up to date; current. 

  • Present; current. 

conj
  • Since, because, in light of the fact; often with that. 

past

noun
  • The period of time that has already happened, in contrast to the present and the future. 

  • The past tense. 

adj
  • Of a period of time: having just gone by; previous. 

  • Having already happened; in the past; finished. 

  • Following expressions of time to indicate how long ago something happened; ago. 

  • Of a tense, expressing action that has already happened or a previously-existing state. 

prep
  • Beyond in place or quantity 

  • Any number of minutes after the last hour 

  • Having recovered or moved on from (a traumatic experience, etc.). 

  • No longer capable of. 

  • Passing by, especially without stopping or being delayed. 

adv
  • In a direction that passes. 

How often have the words now and past occurred in a corpus of books? (source: Google Ngram Viewer )