hyphenate compound adjectives

[rebcabin]

I noticed "single object category" a couple of times in the description of monoids. This must be hyphenated as "single-object category" by the punctuation rule requiring hyphenation of compound adjectives to prevent ambiguity and the slowing down of readers, who must read the sequence twice to decide whether the writer meant a single category of "object" or a category of a single object. See rule 5.93 of the 15th edition of the Chicago Manual of Style. See the style guides of the AMA and of the APA. See https://en.m.wikipedia.org/wiki/Compound_modifier. See Myron's Grammar Hammer https://www.unmc.edu/pharmacology/_documents/Toews-Grammar-Hammer-All-For-ASPET.pdf. Consider the canonical example "small animal hospital;" does it mean a small hospital for animals or does it mean a hospital for small animals?