1005110 jmdict A [id=2208449]

さあ[ichi1]；さー[spec1]；さぁ[sk]
[1][int]
  [note="used to urge or encourage others"]
  come (on); come now; come along; here
[2][int]
  [note="indicates resolve"]
  all right; right; okay; now; here goes
[3][int]
  [note="indicates uncertainty or hesitation"]
  well; hmm; uh; let's see; I'm not sure
[4][int]
  [note="said when something arrives, starts, finishes, etc."]
  here; now; there (we go); ah; oh
[5][int]
  [note="used when interrupting someone"]
  about that, ...; actually, ...