Looking on the internet deeply has found these results:

slowing is the most popular phrase on the web.

slowering 114,100 results on the web	slowing 135,400,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Like showering in a Mexican jail. You see, you're glowering again. Your idea sounds better than showering alone. Seeking an instance of someone showering in clothing is... She's a nightmare, three hours and wouldn't say a word, just sat glowering because she thought I'd nicked her special stapler. I ordered while you were showering. Not advice on showering with him. Nothing but a slab of bread, cheese and sauce growing cold on the counter under the glowering glare of Mr. Sonny Pippilito, my boss.	75 southbound due to construction work... B12 deficit rectified, but her heart's slowing even more. It's this weather slowing everyone down. Kayla's repeat E.E.G. shows diffuse slowing consistent with a permanent vegetative state. Her C.S.F. studies show a slowing of flow, not a complete obstruction. Some minor slowing on the I The V.E.P. indicates slowing of the brain. Heart rate slowing, Adrenal glands normalizing.

slowering

114,100 results on the web

slowing

135,400,000 results on the web

More popular!

Like showering in a Mexican jail.
You see, you're glowering again.
Your idea sounds better than showering alone.
Seeking an instance of someone showering in clothing is...
She's a nightmare, three hours and wouldn't say a word, just sat glowering because she thought I'd nicked her special stapler.
I ordered while you were showering.
Not advice on showering with him.
Nothing but a slab of bread, cheese and sauce growing cold on the counter under the glowering glare of Mr. Sonny Pippilito, my boss.

75 southbound due to construction work...
B12 deficit rectified, but her heart's slowing even more.
It's this weather slowing everyone down.
Kayla's repeat E.E.G. shows diffuse slowing consistent with a permanent vegetative state.
Her C.S.F. studies show a slowing of flow, not a complete obstruction.
Some minor slowing on the I
The V.E.P. indicates slowing of the brain.
Heart rate slowing, Adrenal glands normalizing.