hyperfine meaning
ENFR hyperfine 
- AdjectiveCOMmore hyperfineSUPmost hyperfinePREhyper-SUF-ine
- Extremely fine, especially of the hyperfine structure in the spectra of atoms and molecules.
- Extremely fine, especially of the hyperfine structure in the spectra of atoms and molecules.
Definition of hyperfine in English Dictionary
- Part-of-Speech Hierarchy
- Adjectives
- Morphemes
- Prefixes
- Words by prefix
- Words prefixed with hyper-
- Words prefixed with hyper-
- Words by prefix
- Prefixes
- Adjectives
Source: Wiktionary
Grammatically, this word "hyperfine" is an adjective. It's also a morpheme, more specifically, a prefixe.