Composite colour strings in English: adjectival or nominal?

This paper looks into the category membership of colour words that enter into combination with modifiers like bright, dark, light, or pale. The English grammatical literature usually assumes that these ‘composite colour strings’, used attributively or predicatively, form adjective-adjective compounds. Closer scrutiny, however, reveals difficulties with this view. First, it is unusual for adjectives to modify adjectives. Second, even if they are compounds, it is unusual for their comparative and superlative inflections to be marked not on the head of the structure, but internally on the modifier, as in brighter red. These difficulties lead us to question the compoundhood of those strings, but also to explore the possibility that, at least in some predicative and attributive uses, the colour words in them are nouns. Using data from the BNC and COCA, we test our intuitions and those found in the literature. We conclude that the adjective-adjective compound analysis of composite colour strings cannot be generalised to all predicative and attributive uses. In at least some of those, the colour word is a noun. In some other cases, it may not be possible to decide if the colour word is a noun or an adjective.