raineach

From Temuairian Botany Book:

A particular fern is found in the Eastern Woodlands. The tuatha called them 'raineach'.
The Fae of the woods are said to use these fronds to fan favorable winds upon their loved ones. Oh how I remember days gone by, resting in the vales of the wood, watching the faeries flutter to and fro waving these frond fans whimsically to each other.
I was lucky enough to be caught in one such gust in my youth. I must admit, a most refreshing breeze comes from waving these leaves.