I was wondering why in some cases, both phrases mean the same thing, and one phrase has the plural -s and the other does not?

Collecting stamps (plural -s)
Stamp collecting (no plural -s)

Is that in the 1st scenario, the word "stamps" is a complement to the gerund "collecting" and in the 2nd scenario, "stamp" acts as an adjective and the linguistic structure of an adjective does not have the plural -s?

  • Using a plural noun as a modifier is not usually done. But it's becoming more popular. – Arm the good guys in America Oct 30 '17 at 5:28
  • Not quite. In "collecting stamps", "collecting" is a verb and "stamps" its direct object. In "stamp collecting", "stamp" is not an adjective, but a noun functioning as modifier of the noun "collecting". – BillJ Oct 30 '17 at 8:02
  • I'm still trying to work out why there are donkey sanctuaries but dogs homes. Is it purely a function of ease of pronunciation? / 'Collecting stamp' would sound ridiculous. But the singular-form attributive is the usual choice. 'Car owners' not 'cars owners'. – Edwin Ashworth Oct 30 '17 at 10:10
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    Addressed at When are attributive nouns plural?. There are other threads addressing the normal use of singular-form nouns as attributives, for instance here. – Edwin Ashworth Oct 30 '17 at 10:17
  • After researching (looking on wikipedia that is), I found that modifier is an optional part of a phrase or clause: en.wikipedia.org/wiki/Grammatical_modifier and a complement is one that is detrimental to the meaning of a phrase or clause. In both cases, isn't "stamp" or "stamps" necessary for full understanding of the phrases? Well, and the attributive noun plurar is interesting as well, I will look further into this. Thank you all – Dat Oct 30 '17 at 11:16