Sentence:  Such an <WSD>instrument</WSD> is expected to be especially useful if it could be used to measure the elasticity of heavy pastes such as printing inks , paints , adhesives , molten plastics , and bread dough , for the elasticity is related to those various properties termed `` length '' , `` shortness '' , `` spinnability '' , etc. , which are usually judged by subjective methods at present . 
Meaning of the word marked with <WSD> tags:  a device that requires skill for proper use