shear

For the verb: "to shear"

Simple Past:	sheared
Past Participle:	sheared, shorn

Concise Oxford English Dictionary © 2008 Oxford University Press:
shear/ʃɪə(r)/

▶verb (past part. shorn or sheared)

• 1 cut the wool off (a sheep or other animal).

  ■ cut off with scissors or shears.

  ■ (be shorn of) have something cut off.

• 2 break off or cause to break off, owing to a structural strain.

▶noun a strain produced by pressure in the structure of a substance, when its layers are laterally shifted in relation to each other.

– derivatives
shearer noun.

– origin OE sceran, of Gmc origin, from a base meaning ‘divide, shear, shave’.

usage: On the confusion of shear and sheer, see usage at sheer2.