The Free On-line Dictionary of Computing (30 December 2018):

Address Strobe

    (AS) One of the input signals of a memory device,
   especially semiconductor memory, which is asserted to tell
   the memory device that the address inputs are valid.  Upon
   receiving this signal the selected memory device starts the
   memory access (read/write) indicated by its other inputs.

   It may be driven directly by the processor or by a memory
   controller.

   (1996-10-02)