Is the word you want shear or sheer? As we'll see, these words could be distantly related. Let's take a closer look.
The verb shear - the one with the "a" - means to cut; more specifically, it's often used to mean "to cut the hair from someone or something." One common use is to describe the removal of wool from sheep, but it can be used for cutting human hair as well:
As glad as Hakkai was to see Gojyo again, he was startled by how short his friend's hair was. What had inspired him to shear it off that way?
You should note that the formation of this word is irregular as it moves into the past:
When Goku saw Gojyo's closely shorn hair, he burst out laughing.
The word sheer - the one with the double "e" - actually has several very different usages. In referring to fabric, it means "very thin" or "gauzy":
Sanzo's full set of priestly vestments included a short, sheer veil, held in place by a small golden crown.
On the other hand, it's also an intensifier, meaning something like "absolute" or "apart from anything else":
"Hey, Blondie! Gimme one of your smokes. I'm fresh out," said Gojyo. Sanzo glared, annoyed by Gojyo's sheer effrontery.
Half a dozen bodies already littered the clearing around Goku, but the youkai kept coming, apparently intending to overwhelm him by sheer force of numbers, if nothing else.
More specifically, it can also refer to landscape features that have "great and continuous steepness" (
Webster's):
As they drove into Tibet, the landscape became impressive but ominous, with towering mountains and sheer cliffs.
Finally, as a verb, sheer can mean "to deviate from a given course":
The mountain roads all began to look the same, mile after mile of gradually rising cuts back and forth across the face of Tibet. Then Jeep sheered abruptly, and they ended up precariously stuck at the edge of a steep drop.
"What the hell was that?" snarled Sanzo.
It's this last usage that connects double-e sheer with shear: Webster's hypothesizes that this comes from an alternate spelling of shear, with the idea that the path of a thing that has sheered has cut away from its intended route. On the other hand, sheer meaning diaphanous or pure seems to come from roots that mean "pure" or "shining."
Given all these various meanings, it's hard to come up a mnemonic for remembering which of these is which. Perhaps one could think of the hapless cartoon victim falling from a sheer cliff (with the double "e") and screaming "Eeeeeeeeeee!" ... perhaps with a gauzy, sheer veil flapping from his head. On the other hand, if one is rounding up and manhandling sheep in order to shear them, they will no doubt be going "Baaaa!" (with an "a").
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And sorry for the lateness here! :-(