Sentence:  [C]ataract surgery has been employed for more than 20 centuries. The primary surgical technique for the large majority of this time was a procedure called <WSD>"couching</WSD>". The first written description of <WSD>couching</WSD> is from an Indian surgeon, w:Sushruta 
Meaning of the word marked with <WSD> tags:  An early, largely obsolete, method of treating a cataract by using a sharp object to displace the opaque lens in the eye.