Shimotsuki kagura is kagura (sacred music and dance performed at shrines) that is performed in November (according to the old lunar calendar; December through to January of the following year according to the Gregorian calendar).
霜月神楽（しもつきかぐら）とは、11月_(旧暦)（グレゴリオ暦の12月から翌年1月）に行われる神楽のこと。