absolute block system
Also found in: Acronyms.
absolute block system
[′ab·sə‚lüt ′bläk ‚sis·təm] (civil engineering)
A block system in which only a single railroad train is permitted within a block section during a given period of time.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.