In this paper, the attenuation process of a laser-induced plasma shock wave
(LPSW) has been theoretically discussed and a viewpoint that the weak limi
tation of a LPSW is an acoustic wave is suggested. On the basis of the theo
retical discussion, a definition of a laser plasma acoustic wave (LPAW) is
given. The transition from LPSW to LPAW is also observed on a well-designed
experimental set-up.