These days we mostly say widdershins, but in the Old Language of the Hwicce, the original Tribe of Witches, it used to be withershins, and that's a word to conjure with.
In those days, you were either with or wither: for or against.
Widdershins is a wither-sithe: a journey or going against.
And that way lies power.
Doing things backwards is an old, old magical technique to raise power. Think about it. Backing up is harder and more dangerous than moving forward. It takes focus. It takes concentration. You really have to think about what you're doing.
Going against the grain creates tension, and tension raises power. Believe me, you've never heard the Charge of the Goddess until you've heard it backwards.
Witherwards, one could say: dancing back-to-back, as we still do at the sabbat.
Hence our reputation for creative blasphemy. But this is no mere blasphemy for blasphemy's sake. Oh no: this is blasphemy for a purpose.
Wither isn't just a preposition. It's also a noun: opposition, hostility, adversity. It's a verb: offer resistance, fight, struggle. As an adjective, it means contrary, opposite, wrong.
Hence, witherly: contrary, perverse. To be witherful is to be hostile or wicked, but also to be bold or valiant.
In the Witches' Bible, the Antichrist was known as the Witherchrist. And the God of Witches was called—among his many names—the Witherwin: the Opposer.
Any witch could tell you why.
The Northern ancestors knew the magical technique of raising power by inversion as the Way of the Crawfish, because crawfish swim tail-first.
So come, take my hand and let's dance back-to-back like the crawfish swim, like the witches dance, and just watch the toes of those White-Lighters curl up in response.
Backwards, of course.