I see the term "parts maker" in use a lot in automotive industry news, and I'm wondering if the term is a correct construction (grammatically speaking).
When this term is used in Japanese it is always written with an S sound on the end (whether talking about one or more than one): パーツメーカー So this may contribute to the frequent inclusion of the S in English as well - at least in documents translated from Japanese. However, such cases most likely represent a relatively small percentage.
Web searches produce inconsistent results. Note this Wikipedia page, for example:
There are subcategories here such as "Motorcycle parts manufacturers" and "Automotive part retailers". So depending on the word that follows "part", the S may be included or excluded.
Let's compare the usage using Google Trends:
Maker:
Supplier:
Manufacturer:
Why is there so much inconsistency here? And what do English scholars have to say about this?


