adverb, adverb taking the 'to' particle, noun or participle which takes 'suru'
pleasantly cool; chilly
Describes a refreshing, mild coolness, often of air, water, or a surface. Conveys a pleasant sensation, unlike 冷たい which can be harsh.
朝の空気がひんやりしていて気持ちいい。
The morning air is pleasantly cool and feels nice.
I put a cool towel on my neck.