Strap

No standards body, museum or law opened for this entry defines a watch strap, and nor does the trade's own teaching material. The British Horological Institute (a professional horological body rather than a standards authority) mentions straps in the glossary of its Practical Clock and Watch Servicing Distance Learning Course Technician Grade only inside another entry, defining lugs as "Projections on wrist watch cases supporting the strap or bracelet." That pairing is the whole of the distinction: a strap and a bracelet are alternatives at the same fitting, and neither is defined.

Manufacturers' own specifications show what the word carries in practice. Omega's specification for Speedmaster Moonwatch Professional reference 311.33.42.30.01.002 lists a "Leather strap" whose surface is "Alligator leather" and underside "Non-grained calf leather", closed by a "Foldover clasp". Other materials are described the same way: the Seiko Museum's account of the 1975 Professional Diver's 600m watch, written by its development leader and designer Taro Tanaka, records that the team "adopted polyurethane for the material of the strap, in place of the PVC plastic".

The Federation of the Swiss Watch Industry publishes the Illustrated Professional Dictionary of Horology, "originally compiled by G.-A. Berner and published in 1961" and now carrying "more than 6,000 entries", which FH calls "a genuine reference for the watchmaking industry and a valuable translation tool". It is a trilingual dictionary rather than a standard, and its individual entries could not be opened while this page was prepared, so nothing is quoted from it here. On the evidence gathered, "strap" is an ordinary word the industry uses precisely and has never had to define.