To shear is to cut — shearing sheep, and in engineering a shear force. Sheer means utter (sheer nonsense), very steep (a sheer drop) or very thin (sheer fabric). Cutting takes the A; everything else takes the double E.
The core difference
A verb of cutting and an adjective with three senses.
- shear — cut: shear a sheep, shear bolt, wind shear.
- sheer — utter: sheer luck; steep: a sheer cliff; thin: sheer curtains.
The technical sense
Shear is a precise engineering term — a force acting parallel to a surface, causing layers to slide past each other. Wind shear, shear strength and shear stress all use it, and all take the A.
The irregular past
Shear has an irregular past participle: shorn, as in shorn of his authority. Sheared is also used, particularly in the engineering sense — a sheared bolt.
Frequently asked questions
Which spelling means to cut?
Shear, with the A.
What is wind shear?
A change in wind speed or direction over a short distance — using the engineering sense of shear.
What is the past tense of shear?
Sheared, with shorn as the traditional past participle — as in "shorn of his authority".