Use of adjectives in compound nouns

Question

Here are two compound nouns

1. Heavy pipe fitting works.
2. The biggest pipe fitting works.

In the first compound noun the adjective heavy qualifies the first noun pipe. But in the second compound noun, the adjective biggest qualifies the second noun works, while the place of both the adjectives in both the sentences is same.

1. I want to know what the rule is of using adjectives with compound nouns. How do I know which adjective qualifies which noun?
2. What is meant by works? In what sense has it been used. Is it plural or singular? I tried to search this word on the internet and in a dictionary but found nothing.

Answer 1

1. I don't believe there is a particular rule. The association is primarily based on meaning, and in cases where meaning is not obvious, ambiguities can arise. That is not to say that there is a preferred pattern, such as eg left-to-right. In your first example, (((heavy pipe) fitting) works), it is fairly clear that only the pipes can be heavy. So interpreting the phrase structure is easy. The second one, (biggest ((pipe fitting) works)) makes more sense than (((biggest pipe) fitting) works), unless it is clear from context that the works is only fitting the biggest pipes. Also, the definite article favours the first interpretation.

2. Works here is used in the sense of "factory". An online etymological dictionary states it's "[m]eaning "industrial place" (usually with qualifying adjective) is from late 15c." While the form itself is plural, it would be used in the singular to apply to a particular factory (which might contain multiple workshops). For example steel works, locomotive works, or company names such as Hawthorne Works or Baldwin Locomotive Works.