This document specifies the terms and definitions used in the ISO 22074 series of standards related to rail fastening systems. NOTE In this document, there are some entries where more than one term is listed in the header (e.g. sleeper, tie, cross tie in 3.2.3). In such cases, the first term is the preferred term, generally used in the ISO 22074 series of standards. The other terms are also in common use in the railway industry and are considered to be synonymous (admitted terms).