Oxford Dictionaries has this example under ADJECTIVE 'lightning':
(1) Roman is lightning quick and improving every day in practice, and Bean showed playmaking ability in the preseason.
The adjective is categorized in the dictionary as [ATTRIBUTIVE], which the same dictionary defines as:
(Of an adjective or other modifier) preceding the word that it modifies and expressing an attribute, as old in the old dog (but not in the dog is old) and expiry in expiry date. Contrasted with predicative.
At first glance, this lightning in (1) does not seem to be used attributively. For starters, the quick clearly is not a noun modified by the lightning. Then, is it used predicatively somehow not following the dictionary's own categorization as [ATTRIBUTIVE]?
The only possible way to make that happen is as if the lightning were in coordination with the quick. But that's unlikely, because without the quick, it sounds funky:
(1a) Roman is lightning and improving every day in practice, and Bean showed playmaking ability in the preseason. (?)
Merriam-Webster Learner's Dictionary says that lightning in similar cases is an adverb:
— lightning adverb
— used in combination
(2) an athlete with lightning-quick reflexes
(3) making lightning-fast adjustments
This just sounds absurd.
And I'm thinking maybe it's just a noun. But I need some feedback on this. Any thoughts?
Best Answer
"lightning" is primarily a noun and you can use it in a formula such as "as quick as lightning" or shorter "quick as lightning". In this special case we have an even shorter formula "lightning quick", in which the noun was placed before the adjective quick. In German we have the same formulas:
schnell wie der Blitz - "quick/fast as the flash" (translation word for word)
blitzschnell - "lightningfast" (written as one word")
As to German it is easy to say something about the word class of blitzschnell. The whole is a compound adjective with a noun as combining form in the first part.
As to English you get a bit into a jam and I should say it is subject to individual interpretation. Furthermore, there are two ways of looking at this composition "lightning quick": You can ask what kind of word class is the first element and I should say it is a noun. As to the whole composition I think there will be divergent views. I should say the whole composition acts as a compound adjective with the first element still being a noun as combining form.
(Mari-Lou A will not forgive me that I have drawn attention to a German expression that is parallel to an expression in English. I have tried to abstain from mentioning German, but sometimes the comparative method can make things clearer.)