H2287 חָגַג (khaw-gag')

KJV renderings: celebrate, dance, (keep, hold) a (solemn) feast (holiday), reel to and fro.
Strong's definition: properly, to move in acircle, i.e. (specifically) to march in asacred procession, to observe afestival; by implication, to be giddy
Derivation: a primitive root (compare H2283 (חָגָא), H2328 (חוּג));

From James Strong's public-domain dictionaries (H), JSON edition by OpenScriptures (CC-BY-SA). Every dotted-underline word in the text links here.