noun, noun which may take the genitive case particle 'no'
outstanding popularity; extremely popular
Describes something or someone that is exceptionally popular, often used in advertisements, reviews, or casual praise.
The ramen at this shop is extremely popular.
She is an outstandingly popular figure in the class.
人気 means 'popularity' in general, while 人気抜群 emphasizes that the popularity is exceptionally high.
抜群 means 'outstanding' or 'preeminent' and can combine with other nouns (e.g., 成績抜群 'outstanding grades'). 人気抜群 is a specific compound meaning 'outstanding popularity'.
Compound of 人気 (にんき, 'popularity') and 抜群 (ばつぐん, 'outstanding'). The exact historical derivation is uncertain, but the combination is transparent.