Source : WordNet®

access time
     n : (computer science) the interval between the time data is
         requested by the system and the time the data is provided
         by the drive; "access time is the sum of seek time and
         rotational latency and command processing overhead"

Source : Free On-Line Dictionary of Computing

access time
     
         The average time interval between a
        storage peripheral (usually a {disk drive} or {semiconductor}
        memory) receiving a request to read or write a certain
        location and returning the value read or completing the write.
     
        (1997-06-14)