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Ok, I'm writing a story where the character visits a museum. Does she visit:

  • the mammal exhibit
  • the mammals exhibit
  • the mammals' exhibit

marked as duplicate by Drew, TimLymington, Edwin Ashworth, BladorthinTheGrey, user140086 Dec 27 '16 at 10:38

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  • When front-forming compounds, the singular is preferred (for families and higher categories, if memory serves). I believe this is published advice in international naming conventions, but it didn't fall out of my quick search. – Phil Sweet Dec 26 '16 at 23:06
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    ... and there is a question dealing with attributive vs possessive structures. This is really 3 questions (A or B; B or C; C or A?) all of which have been addressed before. Granted, individual examples may buck the usual trend, but they can be researched for idiomaticity by the OP. Though here, admittedly, the plural attributive is more common in a Google search, apparently because it occurs in compounds / collocations. – Edwin Ashworth Dec 27 '16 at 0:25

the mammal exhibit

Mammal is often used in this way. See the Oxford English Dictionary. I quote the adjectival definition in full in case you can't access the OED.

B. adj.2

(attrib.). Of, relating to, or of the nature of a mammal or mammals.

1840 C. S. Rafinesque Amenities of Nature in Good Bk. No. 1. 9 The sucklers or mammal animals.

1844 R. Chambers Vestiges Nat. Hist. Creation 201 In the mammal fœtus,..the organ has the form of a prolonged tube.

1879 tr. Haeckel Evol. Man I. i. 3 Amphibian and Mammal forms.

1902 Pop. Sci. Monthly Sept. 436 A whale may be alluded to as a gigantic mammal or a mammal giant.

1957 P. J. Darlington Zoogeogr. vii. 469 A small fraction of the Oriental mammal fauna extends for a considerable distance across Wallace's Line.

1988 Conservation Biol. 2 336 Species richness of small mammal communities..directly correlated with shelterbelt length.

1994 Nature 24 Mar. 298/2 This island-continent has until now yielded no confirmed pre-Holocene mammal fossils.

Similarly, your character might visit the reptile house at the zoo. In his comment, below, @sumelic gave a technical explanation of this usage.

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    Some might dispute that the word mammal "is an adjective" in phrase like "mammal exhibit". One thing to note is that pretty much any noun, no matter whether it is listed like this in the dictionary or not, can be used attributively before another noun with the meaning "Of, relating to, or of the nature of [noun]". For example, an "arrowhead exhibit" could be used to mean "an exhibit of, relating to, or of the nature of arrowheads." It seems odd to say that because of this, dictionaries should list "arrowhead" as an adjective meaning "Of, relating to, or of the nature of arrowheads". – sumelic Dec 26 '16 at 23:04
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    A relevant question about what I'm talking about: What is the difference between a part of speech and a syntactic function / grammatical relation? – sumelic Dec 26 '16 at 23:05
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    I'd think 'mammals exhibit' far more likely than 'mammals fauna', 'mammals form', 'mammals fœtus'; logic plays a part in the idiomaticity of attributive modification. In fact, there is possibly as much evidence of 'mammals exhibit' as of 'mammal exhibit' online. – Edwin Ashworth Dec 27 '16 at 0:33
  • "mammary" exhibit? :) Mammary is an adjective! – Chowzen Dec 27 '16 at 1:23

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